Probability distributions, expectation and variance

There are 16 NRICH Mathematical resources connected to Probability distributions, expectation and variance
What's your mean?
problem
Favourite

What's your mean?

Age
16 to 18
Challenge level
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Can you work out the means of these distributions using numerical methods?
Aim high
problem
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Aim high

Age
16 to 18
Challenge level
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How do you choose your planting levels to minimise the total loss at harvest time?
Spinners
problem
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Spinners

Age
16 to 18
Challenge level
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How do scores on dice and factors of polynomials relate to each other?
Random inequalities
problem
Favourite

Random inequalities

Age
16 to 18
Challenge level
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Can you build a distribution with the maximum theoretical spread?
Stats statements
problem
Favourite

Stats statements

Age
16 to 18
Challenge level
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Are these statistical statements sometimes, always or never true? Or it is impossible to say?
Time to evolve 2
problem
Favourite

Time to evolve 2

Age
16 to 18
Challenge level
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How is the length of time between the birth of an animal and the birth of its great great ... great grandparent distributed?
A well-stirred sample
problem

A well-stirred sample

Age
16 to 18
Challenge level
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Typical survey sample sizes are about 1000 people. Why is this?
Binomial conditions
problem

Binomial conditions

Age
16 to 18
Challenge level
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When is an experiment described by the binomial distribution? Why do we need both the condition about independence and the one about constant probability?
Binomial or not?
problem

Binomial or not?

Age
16 to 18
Challenge level
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Are these scenarios described by the binomial distribution?