Saturday, January 16, 2010

Lets count the fingers again

Lets count the fingers again, but
a little different. Use both hands,
Start with one as the little finger of the
left hand. Count left to right so the left thumb is 5.

Continue with the right hand. But lets suppose the right
thumb is missing. 6 is the right index finger, and 9 is
the right little finger.

Don't recount the little finger so 10 is the right
ring finger.

Just keep counting all nine fingers left to right then
right to left. Which finger is # 123456789 ?

Need help? lets count to 17

Left Little" '1
Left Ring" '2
Left Middle" '3
Left Index" '4
Left Thumb" '5
Right Index" '6
Right Middle" '7
Right Ring" '8
Right Little" '9
Right Ring" '10
Right Middle" '11
Right Index" '12
Left Thumb" '13
Left Index" '14
Left Middle" '15
Left Ring" '16
Left Little" '17

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Friday, August 21, 2009

Graham's Number

Not a problem. Just for interest.
If you thought you knew what a big number is, then you may be in
for a surprise and a headache. Follow this link:
http://en.wikipedia.org/wiki/Graham%27s_number

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Friday, June 19, 2009

where would I eat my food

after 7 hours and fifteen days where would I eat my food

Warning: puncuation omitted.

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Friday, April 24, 2009

The Rhetorical Question

"If it takes 1 & 1/2 men, 1 & 1/2 days," says Punnish strutting about in imitation of his master, "to pot 1 & 1/2 geraniums in 1 & 1/2 pots, how many will 2 & 1/2 men pot in 6 days?"

He is rather shocked to hear Pembish answering this rhetorical question from with in the greenhouse.

What, incidentally, is the answer ?

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Friday, February 20, 2009

The Value

110+210 +310 +410.... +100010 = ?

Believe it or not famous Mathematician Jakob Bernoulli determined the value in less than 10 minutes.

How long will you take ?

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Friday, February 6, 2009

King and the Goldsmith

King had given a goldsmith some gold and asked him to make a wreath from it. When the goldsmith finished the wreath, he suspected the crafty goldsmith had pocketed some of the gold and replaced it with some cheaper metal. Yet the wreath weighed exactly the same as the original gold.

How could the fraud be proven ?

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Monday, December 22, 2008

Snowflakes

Shetty, Sameer, Sandeep, and Rajesh planned for a reunion at Minneapolis MN in the weekend. There they come across a unique kind of snowflakes, which according to Sameer, happens only at this time of the year, that too at a very unique temperature and when air flows in a very unique speed.

After returning, Rajesh, still intriqued by the phenomenon called Sameer to ask what was the temperature which caused the Snowflakes of such design and what was the air speed, to which Sameer gave two numbers. When Rajesh enquired whether the temperature was in Fahreheit or Centigrade and the speed kilometer per hour or miles per hour, to his astonishment Sameer said:

"It absolutely makes no difference !"

How ?

- Bob (Robert)

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Friday, December 19, 2008

Doomsday

The Planets Zylon, Tylon and Fylon moved in a circular orbit around the dwarf star Celion, with orbital period of three, four and two earth years respectively. In the year 2001, the four celestial bodies all lies along the straight line.

The next such event would cause a doomsday for these planets. When do you think this will happen.

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Friday, December 12, 2008

Elementary, My Dear Watson

"Watson the facts are the killer began to climb the Mammoth mountain exactly at sunrise, the narrow path is, no more than a foot or two wide, spiraled around the mountain to the glittering hotel."

But remember Sherlock, "the killer might have ascended with varying rates of speed, stopping occasionally along the way to rest." added Watson.

"Thats right and he reaches the summit shortly before sun set."

"But, even if we say that, at night he does his job and come sunrise, he starts his journey back.", "how can you assume that there is a spot along the path that the killer will occupy on both trips at precisely the same time ?"

"Elementary, My Dear Watson !"

It might be elementary for Sherlock holmes but can you prove that ?

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Friday, December 5, 2008

Perpetual Motion

There is a Swinging Bird Toy which is suppose to be in Perpetual motion. See Figure.


The Bird dips its beak in the water and having "drunk its fill" swing back into its upright position. After a while it slowly leans over to dip its beak in the water again, "drinks" and swings back.

Is this really Perpetual Motion ? How this "Perpetual" Motion works ?

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Friday, October 24, 2008

Going in Circles

Bob: ToM Puzzles are not so difficult now a days
Alice: Are you guys able to solve it all
Ted: Except the one when I am too busy
Alice: I have heard that before, you are not busy now

The Circle have three distinct points P,Q, and R. Question is to find another point "S" in the circle so that another circle can be inscribed in the Quadrilateral obtained.

You only have a scale and a compass.

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Friday, September 26, 2008

Kinematics

A dirt-biker rode the first half distance of the race with the speed of 200 miles per hour. For the remaining part he was a bit distracted and covered half the time with the velocity 150 miles per hour and rest of the time, speed up to 250 miles per hour.

If he came second and was beaten by 20 seconds. What was the average velocity of the guy, who came first ?

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Friday, September 12, 2008

Fair Enough

Two brothers had a flock of sheep which they sold getting as many dollars, for every sheep as there were sheep in the flock. Intending to share the amount equally, the older brother and then the younger brother, took from it $ 10 each, alternately in succession.

At the last stage, when it was the turn of the younger brother, there remain less than $ 10. the younger brother took this amount and the elder one gave him his new knife for the sharing to be fair.

Now ! YOU tell me, What's the question to be asked, and what is the Answer?

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Friday, August 1, 2008

Notorious Tank Problem

The notorious Tank Problem that one finds in every single collection of arithmetical and algebraic problems. No doubt, you all remember those classic scholastically dry problems of this order:

"The tank has two pipes -- one leading to fill the tank to the brim and the other out. the first needs five hours to fill the tank and the second ten hours to drain it dry. How long will it take the tank to fill up when the stop cocks are out of both pipes ?"




This problem has a venerable history, dating right back some twenty centuries to Heron of Alexandria. Here is one from his collection for your free time in the weekend.

Four Fountains are there and a reservoir vast.
In but one day the first doth fill it to the brim.
The second two days and nights must play to do the same.

The third takes thrice the time as did the first.
The fourth comes last with four days and nights.
Now tell me when the reservoir will fill,
when all four play at once.




It is two thousand years now that the tank problem has posed and -- such is the force of habit ! -- has been solved wrongly in all this time.

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Friday, July 25, 2008

Triangle Trivia

You have a normal paper in which a triangle is inscribed.



For a circular piece of paper, the lines along which you can fold it "in half" (with half the area on each side) are precisely the lines through the center. Triangles are different and folding it exactly in half won't be that easy, even for an expert geometrician like you, would it ?

Do let me know how you do it, and don't assume anything !

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Friday, July 18, 2008

Beautiful Geometry

Sir Ramanujan said "The sides of the triangle is given. You have to find out the radii of the three circles inside the triangle, the three circles touches each other as well as each touches two side of the triangle as shown in the figure."



Take a = 507,
b = 375 and
c = 252

"You have got all of the weekend and the week after to solve the problem"

Can you ?

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Friday, July 11, 2008

Coin confusion

How can you arrange 10 coins into 5 rows of 4 coins each?

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Word Puzzle

Which English 6 letter word can form 7 other words without rearranging the order of any of the letters?

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Friday, July 4, 2008

Magnetic "Perpetual" Motion

In attempts to invent a "perpetual motion" machine the magnet and its power have played a role of no mean magnitude. Ill-starred "perpetual motion" machine inventors have tried might and main to apply the magnet to this end. Here is one such project described back in 17th century by Englishmen John Wilkins, the Bishop of Chester.

A Powerful magnet A is placed on the top of the pillar leaned against which is two inclined grooves M and N, one above the other. The upper groove M has a small hole C at the top, while the lower groove N is curved.



The inventor claimed that the arrangement would operate as follows. A small iron ball B was to be placed on the upper groove. Attracted by the magnet A, it ought to roll upwards. On reaching the hole, it should roll down, be carried up by inertial along the curve D, and find itself again on the upper groove M, from whence, again attracted by the magnet, it should again roll up and drop through the hole, roll down and on to the upper groove, ad infinitum.

This the inventor conjectured, would produce "perpetual motion".

What do you think ? Will it ?

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Monday, June 30, 2008

Why does Rocket Go Up ?

Professor Feynman was teaching the class.
"Even from students of physics one may often hear a totally wrong explanation of a rocket's flight. They claim that it goes up by thrusting itself away from the air with the help of gases formed from gunpowder combustion. That incidentally is what ancients thought-rockets are invented long, long ago."

He added "But if we were to fire a rocket in an airless void it would fly, and even better than in the air."

What's the right explanation ?

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Friday, June 20, 2008

Fantasy & Science Fiction

Isaac Asimov had a 30 years correspondence with Nobel Prize winner Linus Pauling. Pauling read Isaac's science articles in Fantasy & Science Fiction magazine regularly and wrote Isaac whenever he found an error. Here is an interesting excerpt.
From Pauling to Isaac:

I am writing now about your article in the September 1978 issue. On page 123, you say that Amontons and Guy-Lusac observed that if a gas at the freezing point of water, 0 degree Celcius, is decreased in temperature to -1 degree Celcius, then both the volume and the pressure of the gas will decline by 1/274 of the temperature. This is wrong. What you should have said is that _ _ _ I hope you are keeping busy as ever.

What was the explaination?

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Friday, June 13, 2008

A Motorless Underground Railway

If you have read the free travel, you will find this more intriguing. A booklet with the odd title A Motor less Underground, Leningrad-Moscow Railway was once put out. Its author A.A. Rodnykh, suggested a very interesting project .

His idea was to "dig a 600-km-long tunnel, linking up two cities Leningrad and Moscow by an absolutely straight underground line. this could give us for the first time the opportunity to travel along the straight instead of following a curved path as now." He wishes to say that all our roads describes arcs, as they follow the curve of the earth surface, while the suggested tunnel will follow a straight line along a chord (assume earth as a circle).

This project - if ever realized - would possess a unique characteristic. In this tunnel a train move by itself. At each point, since the train is going in the downward direction due to gravity, it will not require a motor. The big tunnel will actually be inclined to some angle with the horizontal ground at both the points.

In such a slanting tunnel every object should swing, due to gravity, to and fro like a pendulum, hugging to the bottom. Inside it a train would move by itself along the rails, its weight doing the work of locomotive. At first the train will move very slowly but with every new second its speed would increase, to reach soon a figure so incredible,that the air in the tunnel would offer a noticeable resistance.

Do you see any flaw in this design, A motorless vehicle can help realize the dream of free travel. Why this is not done yet?

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Friday, May 30, 2008

The Free Travel !

In his satirical History of Lunar States and Empires(1657), the witty 17th century French writer Cyrano De Bergerac describes an amazing thing which had supposedly happened to him. Experimenting one day, he was lifted up in the air with all his retorts. On landing several hours later, he was astonished to find himself not in his own land of France nor even in Europe, but in Canada.

Strangely enough Cyrano De Bergerac believed his transatlantic flight quite possible, claiming that while he was up in the air, the earth had continued to rotate eastwards which is why he had landed in North America and not France.

A very cheap and simple mode of travel, I must say ! Just ascend and stay suspended for a few minutes and you'll return to a totally different place much further westwards. why tie yourself globe-trottin? Simply hover in mid air and wait till your destination reaches you.

What do you say ?

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Friday, May 23, 2008

Back to Square One

This time Mr. and Mrs Smith planned to go around a square track ( remember the pentagon problem). While Mr. Smith runs one side of the square, Mrs. Smith; being young, completes two sides and a diagonal in the same time.

One morning Mr. Smith decided to test Mrs Smith's intelligence. He said "I will cover all four sides of the square and you cover all the tracks twice (all sides and two diagonals). We must start from the same corner and in the same direction and must finish together, moving in the same direction again." Mr. Smith added. "I will only tread my foot on a path which you have already taken and I don't want you to meet me anywhere en-route".

Assume ABCD is the square, can you help Mrs. Smith route the path?

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Friday, May 16, 2008

The Archimedes Problem

Archimedes' greatest achievement was his anticipation of some of the fundamental ideas of calculus. The problem given here is a classic example of a problem that most mathematician today would regard unsolvable without a knowledge of calculus (indeed it is found in many calculus textbooks) but that yielded readily to Archimedes ingenious method.

Two circular cylinders intersect at right angles. If each cylinder has a radius of one unit, what is the volume of solid figure that is common to both the cylinders ?

No Surviving record was found how Archimedes solved this problem. there is, however, a startling simple way to obtain the answer; indeed, one need to know a little more than formula for the area of the circle(Pi times square of the radius) and the formula for the volume of the sphere (Four-thirds Pi times the cube of the radius). It may have been the method Archimedes used. In any case, it has become a famous illustration of how calculus often can be sidestepped by finding a single approach to the problem.

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Friday, May 9, 2008

Pentagon Problem

Every morning Mr. and Mrs Smith, go over a track around a pentagon, each side of which is a mile. Mr. Smith walking and running rates are 2 and 6 miles per hour respectively. The difference between the walking rates of the two is the same as the difference in the running speeds.

They start together from one corner but in different directions. Mr. Smith runs and Mrs. Smith walks till they meet; thereafter Mrs. Smith runs and Mr. Smith walks. They finish together after Mrs. Smith has covered the track twice and Mr. Smith just once.

Where all do they meet and how long do they take to finish?

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Friday, May 2, 2008

Solving a Rubik's Cube

You have a standard Rubik's cube which you bought from ToysRus whose sides can be rotated to change the face of each of the cube. Now assume the Rubik's cube HAVE 27 cubes somehow placed, one upon the other in the 3 X 3 X 3 fashion and solving a Rubik's cube means having same colors at each of the 6 faces.

What are the total number of combination you can get out of a Rubik's cube and how many of these combination is equal to solving a Rubik's cube.

* Note that the corner pieces of the rubik's cube only rotate and align with other corner pieces and so on.

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Friday, April 25, 2008

Escaping the Tunnel

Two boys walking in the woods decided to take a shortcut through a railroad tunnel. when they had walked two-third of the way through the tunnel, their worst fears were realized. A train was coming from the opposite direction, nearing the tunnel entrance. The boys panicked and each ran for a different end of the tunnel. Both boys ran at the same speed, 10 miles per hour. Each boy escaped the tunnel just at the instant that the train would have squashed them into the rails.

Assuming the trains' speed was constant, and both boys were capable of instantaneous reaction and acceleration, how fast was the train going ?

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Friday, April 18, 2008

Still Got Friday

I got on scooter within ten minutes after I got your letter. When I got to Carlsbad, I got a taxi for town. But I got wet through before I got to Carlsbad, and I have got such a cold as I shall not be able to get rid of in a hurry. I got to bank about noon, but first of all I got shaved and dressed. I soon got into the secret of getting a petition before the board, but I could not get an answer then, however I got intelligence from the agent that I should most likely get one the next morning.

As soon as I got back to my hotel, I got my dinner, and got to bed, it was not long before I got to sleep. When I got up in the morning, I got my breakfast, and then got myself dressed, that I might get out in time, to get an answer to my petition. As soon as I got it, I got into the taxi, and got to Carlsbad by three: and about tea time, I got home. I have got nothing particular for you and so Adieu.

What's wrong in the above paragraphs ? Can you fix it ?

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Friday, April 11, 2008

Elementary My Dear

David Taylor drove at a steady speed along the highway, his wife beside him. "Have you noticed," he said, "that those road signboards seem to be regularly spaced along the road? I wonder how far apart they are."

Mrs. Taylor glanced at her wristwatch, then counted the number of signboards they passed in one minute. "What an odd coincidence!" exclaimed Taylor. "When you multiply that number by 10, it exactly equals the speed of our car in miles per hour."

Assuming the car's speed is constant, that the signs are equally spaced, and Mrs. Taylor's minutes began and ended with the car midway between two signs, how far is it between one sign and the other?

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Friday, April 4, 2008

Outside the Box

There are five boxes A,B,C,D, and E each with some oranges in it.

1. Box A has 12 times oranges than in B
2. Oranges in D is 1/2 as in A, and is equal to the product in B & C
3. E, with mid number, is the sum of oranges in C & 1 other box
4. Number of oranges in C is number in A divided by 8
5. One of the boxes contains 4 oranges

Can you find out the numbers ?

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Friday, March 28, 2008

Get Work Done

David Taylor wanted his house painted in two days. One contractor said that he would charge $ 210 and take one full week. Another contractor wanted six days with same charges. the third contractor too was happy about the charges but expressed his inability to finish his work in less than five days.

David Taylor was in a hurry and wanted it done in two days and no more. Accordingly he consulted Johnny Appleseed , a close friend.

"Oh! that is no problem, I will get the work done." said Mr. Appleseed . "It will cost just $ 4 more and you need not worry, I shall pay that out of my own pocket."

What was Mr. Appleseed 's plan?

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Friday, March 14, 2008

Silverfish and the Rubik's cube

Remember the bookworm Silverfish

This time he finds a Rubik's cube made of wood. He starts at the center of face of any one of the outside cubes and bore a path that takes him once through every cube. His movement is always parallel to a side of the large cube, never diagonal.

Is it possible for the Silverfish to bore through each of the Rubik's side cubes once and only once and finish his trip by entering the final central cube for the first time?

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Friday, March 7, 2008

Akbar and Birbal

Akbar used to play chess with Birbal almost every evening. One evening when Birbal won , Akbar was very pleased with Birbal's game and so offered him a grand reward.

"Ask and thou shall recieve. I am rich enough to satisfy thy most cherished wish," snapped Akbar.
Birbal was hesistant but, on being forced by the emperor, said, "Sir, I will like to have one grain of wheat for the first square on the chessboard, two for second, four for third, and so on for all the 64 squares."

"Is that all?" retorted Akbar. "birbal, thy request is not worthy of my generosity. Anyhow, thou shall have thy sack of grain."

What do you think was the size of this sack ?

For the uninitiated, Birbal

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Friday, February 29, 2008

Charlotte's Adventure

Charlotte's* baby Joy flew in the air and got stuck on the other side of the road.

Luckily, a fifteen feet long ladder is placed across the street such that while its base is at one edge of the street its top rests against the opposite wall at a height of nine feet. Similarly, another ladder, twenty feet long, is placed resting across the other side-wall so that the two ladder cross each other.

Charlotte wants to use the ladder to cross the street.

How long will Charlotte take to accomplish the crossing assuming that he covers one foot in ten seconds ?

* Charlotte is the name of the barn spider

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Friday, February 22, 2008

It Could Happen To You

Michael was going to his hometown to see his mother who had fallen ill suddenly. He had been driving through the hills since mid-night. The day had just broken and he was happy to get a view of the country he was passing through. Suddenly he had to jam the brakes when a missing culvert alerted him. He did managed to stop just in time and was glad he had not driven over it during the hour of darkness. Perhaps the culvert had been washed away by rain the previous evening.

After he got over the initial shock, he went about inspecting the site with the idea of finding a diversion but due to the nature of the terrain, any bypassing seemed impossible. It had to be over the missing culvert; but what chances was there of making it, he wondered !

Three meters of the road was not there and the car was five meters long. He noticed that there was a gradual climb of one in ten just before the culvert and that the road on the far side was level with the near end of the culvert. He estimated that his car could pick up a speed of atleast seventy two kilometers an hour just before the jump. It occured to him that he could make it. He had been known to be a brave man; moreover the love for his mother inspired confidence.
"It's now or never," he thought and off he went.

Did he make it ?

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Friday, February 15, 2008

Timeless puzzle

"Boss."
"Yes Tom."
"How long did you take to get home from the office?"
"Well, when I started from the office the hour hand and the minute hand were together and when I got home they had just about got exactly opposite each other."

"And Boss."
"Go on. Tom"
"Had you left the office when the two hands were exactly opposite each other, you would have got here exactly when the two met."

"I don't know, Tom"

Sharp Tom did manage to get the Boss muddled up, but was he right ?

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Friday, February 8, 2008

Fact are facts, Watson !

"As per Inspector Lestrade, the accused house is on the bank of a river which is quarter mile wide and has current of 2 mph". said Dr. Watson

"Don't forget Watson, Just opposite his house, on the other bank, is victims house. The accused can swim across to his house." Sherlock Holmes added.

"But its impossible for him to reach there in less than ten minutes". exclaimed Dr. Watson.

"The fact are, the accused can swims at 2.5 mph in still water and his walking speed also is 2.5 mph."

"Can he do by a combination of swimming and walking?"

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Friday, February 1, 2008

The Billionaire Club

Bill Gates, and Warren Buffett were sitting together in the Billionaire Club with 56 and 52 billion dollars respectively. Suddenly Gates hit upon a new idea.

"We'll throw six dice together," he said.
"If we get two pairs I win, otherwise I lose."
"But what about four or more dice show the same digit?" enquired Warren.
"That makes two pairs; so that too gives me a win."
"And if only three dice have the same digit?"
"You win in that case because it does not make two independent pairs."

"Each games of chance will cost 2 Billion dollars to the looser" added Gates. "You want to play?"

Warren, a little confused calls YOU and asks "Who is more likely to win in this scenario?" What will you say ? Assuming they do play, how many games they can play at the least ?

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Friday, January 25, 2008

Bob and Betty

"You remember I had bought little Tom, a bat and two balls just last week," said Betty to her husband.

"Yes," said Bob, "we had gone together to the market that day."

"Oh! Ofcourse," exclaimed Betty, "Now Tom has sold them to Bunny. He made 20 percent on the bat but has given away the balls, for which we had paid half as much as the bats, at a loss of 20 percent."

"But, mom, you are forgetting that the balls were worn out," interrupted little Tom. "One could not have made profit on them. Anyhow, I made two dollars on the whole and that should not be too bad."

"Well done, son," said Bob; "business will be your line, when you are young."

How much had Betty paid for the bat and for each ball ?

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Friday, January 18, 2008

Fake Records

The Director of Medical Services was on his annual visit to the EENT hospital. He came across the following data for a particular day:

Ear consultations 45; Nose 50; Throat 70; Ear and Nose 30; Nose and Throat 20; Ear and Throat 30; Ear Nose and Throat 10; Total patients 100.

He became very curious and after sometime he commented, "It is no use filling up these registers just before my inspection. You are aware why we maintain these records, and such mistakes cannot occur if these entries are made everyday".

"Sir, I don't think there is anything wrong with the records" replied the Doctor in-charge.

What do you think ?

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Friday, January 11, 2008

The Tortoise and the Hare

Little Johnny was not convinced when his teacher said that the hare would finally overtake the tortoise. He remembers the fable from the bed time stories and was sure that the tortoise always wins the race.

"You said that the tortoise was a thousand meters ahead," said Johnny. "Yes," replied the teacher, "but the hare runs ten times as fast as the tortoise."

"That makes little difference, Sir; because by the time the hare covers those thousand meters, the tortoise would have gone ahead by hundred." "That's right."

"While the hare is over with his hundred, the tortoise would have covered ten meters more. When the hare makes up these ten, the tortoise would have managed another meter. By the time the hare covers this one whole meter, the tortoise would be leading by one tenth of a meter. And while the hare is still at it, the tortoise covers another one-hundredth, and so on. I agree the lead is diminishing and if you carry on it may reduce to one-millionth of a meter or even less but the hare will always be lagging behind."

"No, Johnny, that can't be right as by the time the hare covers two thousand meters, the tortoise covers just two hundred meters and would be eight hundred meters behind."

"Well, Sir, let's not jump into conclusions. I have just explained to you the way I look at the problem and it seems logical.

What do you think ? Don't let the fable affect your decision.

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Friday, January 4, 2008

Rose-red city half as old as Time

Two professors, one of English and one logic, were having drinks in the local bar. "It is curious," said the professor of literature, "how some poets can write an immortal line and nothing else of lasting value. J. W. Burgon, for example. his poems are so mediocre that no one reads them now, yet he wrote one of the most marvelous lines in English poetry: 'A Rose-red city half as old as Time."

The one devoted to "the science that draws necessary conclusions", improvised a brainteaser, then raised his glass and recited.

"A rose-red city half as old as Time.
One billion years ago the city's age
Was just two-fifths of what
Time's age will be, a billion years from now.
Can you compute
How old the crimson city is today?"

The English professor had long ago forgotten his algebra, so he quickly shifted the conversation to another topic, but you should have no difficulty with the problem, right ?

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Friday, December 28, 2007

Miles and Missiles

You are called for the final interview at National Air Force Academy(NAFA). The officer, Sir John Baldwin asks you a single question, which is going to decide your fate.

"Two missiles were shot towards each other. They were 14,600 miles apart when they started. One was moving at 14000 miles per hour and the other at 16000 miles per hour."

"Now listen carefully" he added, "If they collide, that will be the end of the world. You can diffuse them only if you know, how far apart they are one minute before collision. Can you ?"

Sir John paused and added, "Take your time, Sonny."

"If only I had my pencil, paper or calculator." You were thinking.

So, did you passed the test ?

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Friday, December 14, 2007

Ina Meena Dika

Mr. Tito collecting data for census came across a house with three sisters Ina, Meena, and Dika. There were no straight answers when he enquired about their ages. This is what he was told

Ina said "All of us are above 24 years of age, Dika is the youngest, and ofcourse I am the eldest."

"The difference between Dika's age and mine is three years and the sum of my age and Ina's age is two more that twice Dika's age" told mathematician Meena. I am eldest if and only if Dika is not the youngest, she added.

Dika was more "clear" than others , she said "Meena is elder to me" and "Either I am 24 years old or Ina 25 or Meena 26" She added one more piece of vital information "Meena is not 27 years old"

To add to the confusion, Mr. Tito was told by a neighbour that one of the sister always lies and the other two always speak the truth. Can you help him find the ages?

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Friday, December 7, 2007

Toss a coin and see...

The chances of a tossed coin falling head or tails is almost 50-50 with an extremely small chance of it falling on its edge. Therefore what should be the dimensions of a coin that has a probability of 1/3 to fall heads, 1/3 to fall tails, and 1/3 on its edge?

What is one supposed to do after reading this, You could of course pretend you haven’t read it but then who would know you didn’t?

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Friday, November 30, 2007

Dots and planes

Five dots are arranged in space so that no more than three at a time can have a single flat surface pass through them.


If each group of three dots has a flat surface pass through it and extend an infinite distance in every direction,



What is the maximum number of different lines at which these surfaces may intersect one another?

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Friday, November 23, 2007

Alice and Bob

Facts

There are 2 mysterious integers A and B and two logicians Alice and Bob. Both integers are greater than 1 and less than 101. Alice is told the product of two and Bob knows the sum. Neither is told the values.

Conversation

Bob: I cannot determine a, b
Alice: I too cannot determine a, b
Bob: I already knew that.
Alice: In that case, I now know them
Bob: In that case, I too now know a, b.


How is this possible?

btw Happy thanksgiving

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Friday, November 16, 2007

Lucky Number !

Mr. Tito collecting data for census asks the man who answers the door,

"How many kids do you have and their ages?"

The man, a logician thought of playing a trick, replied "I have three children. If you multiply their ages you get 36, if you add you get my house number"

Mr. Tito a bit perplexed, but then smiled and said "that's not enough".

The man said, "I wish i can tell you more but I hear my oldest kid calling."

Mr Tito then says - "Aha ! now i know."

What about you ?

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Friday, November 9, 2007

Want bags full of gold coins ?

"I have got 10 Bags with 100 gold coins each. Each coin weighs 10 gms in 9 bags and each coin weighs 9 gms in one bag"

"I also have a weighing machine which gives you the exact weight "

"I will give you all the bags and all the coins on one condition", said the Jinni.

"if you can use the weighing machine, least number of times, to find out which bag has coins of 9 gms."

Can you ?

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Friday, November 2, 2007

Wine bottle puzzle !

You are a logician turned mad scientist,and decide to have a Party ONE MONTH from today. You have one thousand bottles of wine. Suddenly, you remembered about a "small" experiment you did, which POISONED one of the wine bottle. Ofcourse you don't remember which one.

The poison takes a LITTLE Less than a month to take effect.

You have a LOT of "guinea pigs" at your disposal. The puzzle is to find the SMALLEST number of rodents that must drink from the bottles to find the poisoned one?

HINT: There is one !

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Friday, October 26, 2007

Million dollar question

A logician puts 10,000 dollar in a Weekly trading scheme.

-> About half the time, He makes an 80% gain.

-> The other half, he makes a 60% loss.

One year later, how much money he will have ?

a> 1.95
b> 14,000
c> 140,000
d> 1.4 Million
e> 131 Million

No Marks without explaination !

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Friday, October 19, 2007

And then there were none ?

Three doctors and three patients are traveling together through a jungle when they come to a river.

All the patients have a unique kind of fever which will infect the doctors if at any time the number of patients are more than the number of doctors.

The largest boat available can carry only two people at a time.

The doctors are immune if at any side of the river the body count of doctors are equal or greater than the numbers to patients. otherwise, the doctors gets infected. The doctors can only save the patients if they all reach together safely otherwise, "And then there were none" would be appropriate to say.

Time is running out. How will YOU save everyone's life ?

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Friday, October 12, 2007

Not a Rubik's cube

Here is a problem to stretch your mind.

  • You have a CUBE of dimension 1 inch x 1 inch x 1 inch
  • You put the cube in x, y, z plane such that the coordinates of the cube is (0,0,0) and (1,1,1)
Now listen carefully
  • You cut the cube at three places
  • i> x=y , ii> y=z and iii> x=z

"You" are doing all the work , now you give the answer to the puzzle..

How many parts you cut the cube ?

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Friday, October 5, 2007

Infidelity kills

There is this weird self sufficient island away from our nice world. There's a custom in this island which requires a woman to kill her husband the morning after she discovers that he's having an affair with another woman.

It also happens that every woman KNOWS whether EVERY other man is having an affair or not except her own husband. The Qeer thing is they are NOT suppose to talk to each other about this point. And ofcourse some men in the island ARE having affairs with the wives of other men. So life in this island goes on peacefully since no woman can know for sure that her own husband is cheating on her. Unfortunately, an Oracle visits the island one day and proclaims that at least one man in this island is having an affair.

Question: WHAT HAPPENS AFTER THIS ?

* The interesting thing about this problem is on a first reading the Oracle's info no useful information in the island that has more than one unfaithful man

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Friday, September 28, 2007

Got money, got 7 sons !

An old Man has some savings X.

He has 7 sons.

When he divides the Money equally between two sons one dollar is left

If he divides between three sons equally then too one dollar note is left

Similarly if he divides it equally between four, five and six sons, one dollar is left.

BUT if he divides it between seven sons equally then nothing is left.

And the obvious question is, how much money he had in the savings ?

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Friday, September 21, 2007

"Two Job Offers" Puzzle

Now assume you're so brilliant, that you get job offers usually reserved for the Mensa guys which is the 98th percentile of the current population taking the test.

You've got two offers on hand.

One pays $ 180,000 per year with an annual increment raise of $ 20,000 while the other also pays the basic $ 180,000 per year with a guaranteed $5,000 raise every six months.

you have 30 seconds to decide, which one should you take if you're not actually a schmuck deep down?

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Friday, September 14, 2007

The "Impossible" Puzzle

This puzzle is for those who are aware of the "Mock Turtle"

This is the story of a squid called Sebastian, who ran out of ink. He called his friend, Archibald, who was an octopus, and asked him to buy some more Ink from the printers. So along went Archibald. "That will be 67 pence," said the shopkeeper, as he handed over the bottle of sea blue Ink. Archibald got out his wallet, counted out the money, and handed it over.

But at the end of the day, when the printer counted up his change, he found he was short by 12 pence. "I've been robbed," he cried! A Mock Turtle from the local constabulary was called in, but entertained grave doubts as to whether Archibald really was a thief. "I was at school with the old fellow," he said, "and he never could get the hang of different branches of Arithmetic."

As everyone knows, the different branches of Arithmetic are Ambition, Distraction, Uglification and Derision.

But was the Mock Turtle right about Archibald? Or is his information just a red herring?

Editor's note: There are indeed some red herrings


* And yes Archibald is not a thief

OT: if you are interested in Mock Turtle's story follow

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Friday, September 7, 2007

Sheeps and Three sons

A guy is owner of a certain number of sheeps for god's sakes and also the father of three sons who for some reason are expert logicians. So here comes the question.Clever as you are will think to yourself, now all this guy needs is to believe he's about to die so that he can make a will to divide the sheeps among the sons, right? Right, Except He calls them together (the sons, not the sheeps) and tells them how many sheeps (not sons) he owns AND Adds that

1. The eldest will inherit the most sheeps
2. The youngest the least
3. Nobody having more than 10 sheeps, which as we all know is a crime.
4. He then whispers in each son's ear how many sheeps he personally will inherit.

After that he proceeds from the eldest to the youngest, asking each ALOUD if he can calculate how many sheeps each of his brothers will inherit and each replies, "NO". He does it again and again each replies, "No" But then the eldest son on being asked the question once more says, "Yes, each of the last two 'noes' (that's the plural of 'no') gave me some information, and I now know (no plural of 'knows') how many sheeps each of us will inherit." What's the bet you're already wondering how may sheeps each son will get?

QUESTION IS HOW MANY SHEEPS EACH ONE WILL GET ?

* NO POINTS WITHOUT EXPLAINATION

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