Measures of spread

There are 7 NRICH Mathematical resources connected to Measures of spread
Half a minute
problem
Favourite

Half a minute

Age
11 to 14
Challenge level
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Anna, Ben and Charlie have been estimating 30 seconds. Who is the best?
About Average
problem
Favourite

About average

Age
11 to 14
Challenge level
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Can you find sets of numbers which satisfy each of our mean, median, mode and range conditions?
How would you score it?
problem
Favourite

How would you score it?

Age
11 to 14
Challenge level
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Invent a scoring system for a 'guess the weight' competition.
Spread
problem

Spread

Age
16 to 18
Challenge level
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Given the mean and standard deviation of a set of marks, what is the greatest number of candidates who could have scored 100%?
Maximum Scattering
problem

Maximum scattering

Age
16 to 18
Challenge level
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Your data is a set of positive numbers. What is the maximum value that the standard deviation can take?
David and Goliath
problem

David and Goliath

Age
14 to 18
Challenge level
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Does weight confer an advantage to shot putters?

May the best person win
article

May the best person win

How can people be divided into groups fairly for events in the Paralympics, for school sports days, or for subject sets?