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Feet on the bus

Posted by nordtorp under MathsChallenge (34 Responds)

There are seven girls in the bus. Each girl has seven bags, with seven cats. Each cat has seven kittens.

How many feet are in the bus?

Out of order

Posted by Chris under Logic, Tom (37 Responds)

A drink machine has three options Coke, Pepsi and Random (i.e. Pepsi or Coke).  Each drink is $1.  A friend tells you that the machine is faulty and that all the buttons are incorrect.

How much money would you need to spend to know which buttons deliver which drinks?

Fag problem

Posted by Chris under Logic (17 Responds)

Mr. Striker is walking home across the park.  It is a walk which takes exactly two cigarettes.  In his cigarette case he has two Craven Doodahs and a pair of El-Rashids(which he prefers).

What are the chances of his smoking two El-Rashids in such a walk if he randomly withdraws cigarettes from the case.

Ain’t that the truth!

Posted by Chris under Logic (45 Responds)

Which of the following statements are true and which are false?
1. At least one of these ten statements is false.
2. At least two of these ten statements are false.
3. At least three of these ten statements are false.
4. At least four of these ten statements are false.
5. At least five of these ten statements are false.
6. At least six of these ten statements are false.
7. At least seven of these ten statements are false.
8. At least eight of these ten statements are false.
9. At least nine of these ten statements are false.
10. At least ten of these ten statements are false.

Nov 2011: I added ” and which are false” to the original question.

Clean Shaven

Posted by Spencer under Logic (12 Responds)

In a village, the barber shaves everyone who does not shave himself/herself, but no one else.
Who shaves the barber?

A flipping fortune

Posted by Chris under MathsChallenge (32 Responds)

Starting with $1, you begin flipping a coin. Each time it comes up heads you double your money.  You stop when the coin lands tails up, but you keep all the money.  On average, how much money do you expect to have after one game.  I’ve no idea where the money is coming from.

Example.  You flip HHT, you end up with $4 (including the initial $1).

Seating arrangements

Posted by Chris under MathsChallenge, Tom (24 Responds)

Thirteen friends decide to go to the movies.  In the theater there are rows of 13 seats.  For some stupid reason they decide that the first person to enter the row may sit wherever he chooses.  The second person must sit on either side of him with no empty seat between.  The third person may sit on either side of the first two as long as no empty seat is between them.  This procedure continues until all are seated.

How many different seating arrangements are possible?

Speed of Light in Holy Quran

Posted by TheWyvern under Tom (4 Responds)

This is the answer to my post “The Speed Of  Light.. Read Carefully ..

Behind a great verse, there is a hidden signal to the speed of light. Recently that signal was discovered by scientists, God says :( And verily, a day with your Lord is as a thousand years of what you reckon.)(Sûrat Al-Hajj- verse 47)

In 1969, and during their trip to the moon the astronauts put a glass mirrors on the surface of the moon and scientists on earth sent a Laser beam to be reflected on these mirrors to back again to the earth . By that they calculated the precise distance between earth and moon.
If we observe the moon from outside the solar system , we can see that moon is revolving a complete round around earth every 27.3 day , but because earth revolves around itself so we see the moon is completing the round every 29.5 day

The moon revolves around earth a complete round every month, but because earth is also revolving around itself and in the same direction so that we see the month is 29.5 day but in fact it only takes 27.3days for the moon to complete the round. The question is what is the traveled distance by the moon around earth in 1000 year?

A Muslim scientist put forward an idea which is: the holy verse refers to two equal times and that is some kind of the relatively. God be He blessed says: (And verily, a day with your Lord is as a thousand years of what you reckon) (Sûrat Al-Hajj- verse 47), so we have a day and a one thousand year, how can we make them equal? And what is the common factor?

Scientists consider the speed of light is a distinguished speed and there is no object can be able to reach that speed. So whenever the speed of an object increases therefore the time for that object will slow down. Therefore if any object reached the speed of light, the time will stop for that object. that is the summary of Theory of relativity.

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A photo for the real distance between moon and earth .The moon revolves around earth in a non- circular (Oblate) orbit .Distance between both of them is about 384 thousand km. Moon revolves around earth in a speed of 1 km / second. According to the International standards, speed of the light in the empty space is 299792 km/second.

If we called the mentioned day in the verse with “the cosmic day” to distinguish it from our ordinary day so according to the holy verse (And verily, a day with your Lord is as a thousand years of what you reckon) we can write the equation as the following:

“One cosmic day” = “one thousand year (according to our calculations)”

So, there is a hidden relationship between length of the day and length of the one thousand year. What is the relation?

1. Calculation of the length of the one thousand year

The determination of months and years is based on the movement of the moon. so the month for us is a one complete round for the moon around the earth. We know that moon revolves one round every month around earth, so it will be 12 rounds in the year. God says :( Verily, the number of months with Allah is twelve months (in a year)) (Sûrat at-Taubah- verse 36)

In a simple calculation based on the real month, the moon travels 2152612.27 km around earth in compete round. This distance represents the length of the orbit that the moon takes while a complete round during one month.

So the distance per year is: 2152612.27 × 12 = 25831347 km

And in one thousand year is: 25831347 × 1000= 25831347000 km

2. Calculation of the length of the one day

The day is 24 hours and in seconds it is: 86164 seconds according to the International standards.

Right now, we have the value of one thousand year “25831347000km” which is the distance” and we have the length of the day “86164 second” which is “the time“.

Hence, to realize the hidden relation between distance and time we can use the known formula:

Speed = distance ÷ time

After applying these figures in the formula we can see the surprise which is:

The cosmic speed = 25831347000 ÷ 86164 = 299792 km\ second which is exactly the speed of the light.

Therefore we can realize that the signal in the holy verse is the speed of light by liking “the one day” and “the one thousand year”. this is a scientific precedence for the Qur’an and it wouldn’t be a coincidence.


Here are some questions that the reader of this article may face which can be summarized in the following:

1. Why we considered this verse as a signal for speed of light?

2. Why the Qur’an did not speak directly about the speed of light?

3. Does this research say that the divine order descends in the speed of light?

In fact the Qur’an contain many hidden signs which were Unintelligible in the previous years but at the suitable time it can be explained and became clear to understand the miracle and to be an evidence that message of Islam is sincere.

The holy verse linked between the day and the one thousand year and the relation is the value of the speed of light which is 299792, how can we explain the existence of that number in the Qur’an?

3 squares

Posted by Chris under MathsChallenge (8 Responds)

I’ve pinched this from the old ToM site.

There are three distinct integers which have the property that the sum of any two of them is a perfect square. What are they ?

There is more than one solution.

Flipping coins

Posted by Chris under MathsChallenge (36 Responds)

It’s ages since I’ve seen this one.

After flipping two coins, at least one of them shows heads. What is the probability that the other one also shows heads?

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