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Age 14 to 16 Short
Challenge Level


The mean, median and mode of five numbers are all the same.

If four of the numbers are 7, 7, 5 and 7, what is the fifth number?


This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.
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