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Half a Minute

Age 11 to 14
Challenge Level

Anna, Ben and Charlie have been using the NRICH timer to see who is best at estimating 30 seconds.

They did this five times each and their times in seconds were recorded in the table below.
Anna Ben Charlie
31 36 37
26 19 32
32 39 24
27 36 32
29 20 30

How would you decide who is best at estimating 30 seconds?

If you enjoyed this problem, you might want to have a go at estimating time for yourself - are you better than Anna, Ben and Charlie?

You may also like the problem How Would You Score It?

With thanks to Don Steward, whose ideas formed the basis of this problem.