Conditional probability

There are 26 NRICH Mathematical resources connected to Conditional probability
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problem

Dropouts

Age
14 to 16
Challenge level
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What percentage of students who graduate have never been to France?
Drug testing
problem

Drug testing

Age
16 to 18
Challenge level
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How do different drug-testing regimes affect the risks and payoffs for an athlete who chooses to take drugs?
Non-Transitive Dice
problem

Non-Transitive Dice

Age
11 to 14
Challenge level
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Alison and Charlie are playing a game. Charlie wants to go first so Alison lets him. Was that such a good idea?
Ante Up
problem

Ante Up

Age
16 to 18
Challenge level
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Use cunning to work out a strategy to win this game.
At least one...
problem

At least one...

Age
11 to 14
Challenge level
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Imagine flipping a coin a number of times. Can you work out the probability you will get a head on at least one of the flips?
Mathsland National Lottery
problem

Mathsland National Lottery

Age
14 to 16
Challenge level
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Can you work out the probability of winning the Mathsland National Lottery?
Same Number!
problem

Same Number!

Age
14 to 16
Challenge level
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If everyone in your class picked a number from 1 to 225, do you think any two people would pick the same number?
Dicey Dice
problem

Dicey Dice

Age
16 to 18
Challenge level
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Invent a set of three dice where each one is better than one of the others?
X-Dice
problem

X-Dice

Age
16 to 18
Challenge level
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Explore these X-dice with numbers other than 1 to 6 on their faces. Which one is best?