On average how many rolls does a craps game take if you:

a) win, b) lose and c) either win or lose?

Rules of craps: You use a pair of dice. You make a first roll (the “come-out”

roll). If you get a 7 or 11 (a “natural”) you win. If you get 2, 3 or 12

[...]

1. I give you an envelope containing some money (you may open it if you want). I then offer you another envelope and tell you that it is equally likely to contain either half as much or twice as much money as in the first envelope and ask if you’d like to swap them. Should [...]

I have a pair of special 6-sided dice. One of them has 3 Red sides, 2 Yellow sides, and 1 Blue side. The other has 2 Red sides, 3 Yellow sides, and 1 Blue side. Assume the dice are fair (probability of rolling any face = 1/6).

I pick them up, shake them in my [...]

“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 [...]

Four positive integers which are different from each other total less than 18. To find out the four numbers you need to know their product and the smallest number.

But you don’t know their product and you don’t know the smallest number . . . or do you?

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 [...]

I have a pair of special 6-sided dice. The first has 3 Red sides, 2 Yellow sides, and 1 Blue side. The second has 2 Red sides, 3 Yellow sides, and 1 Blue side.

Assume the dice are fair (probability of rolling any face = 1/6). If I roll them both at the same time, on [...]

The lottery – wouldn’t we all like to win it?

Well there’s a new one in the UK – The Health Lottery. The National Lottery is the other, more ensconced one. Which one of these two should you play?

The statistics…

The Health Lottery

Pick 5 numbers out of a pool of 50

Match 3 – £50

Match 4 – £500

Match [...]

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Maths
A bit boring, but it’s this or nothing.

If I roll a pair of dice and at least one comes up with 1 or 6, what is the probability that they are both 6?

OK here’s one:

A man lives in a 50 floor building on the top floor. In the morning he can go down in the elevator but after work he can’t go back up unless someone’s with him. Why?

Suggeststed by Smart Thyng AKA Gus

(I suspect that everyone knows this one).