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problem
Two's company
Seven balls are shaken. You win if the two blue balls end up touching. What is the probability of winning?
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problem
Cosy corner
Six balls are shaken. You win if at least one red ball ends in a corner. What is the probability of winning?
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problem
Litov's mean value theorem
Start with two numbers and generate a sequence where the next number is the mean of the last two numbers...
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problem
Searching for mean(ing)
If you have a large supply of 3kg and 8kg weights, how many of each would you need for the average (mean) of the weights to be 6kg?
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problem
Last one standing
Imagine a room full of people who keep flipping coins until they get a tail. Will anyone get six heads in a row?
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problem
Same number!
If everyone in your class picked a number from 1 to 225, do you think any two people would pick the same number?
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problem
Mathsland national lottery
Can you work out the probability of winning the Mathsland National Lottery?
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problem
Non-transitive dice
Alison and Charlie are playing a game. Charlie wants to go first so Alison lets him. Was that such a good idea?
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problem
Odds and evens made fair
In this follow-up to the problem Odds and Evens, we invite you to analyse a probability situation in order to find the general solution for a fair game.
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problem
Wipeout
Can you do a little mathematical detective work to figure out which number has been wiped out?
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problem
Unequal averages
Play around with sets of five numbers and see what you can discover about different types of average...