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Age 11 to 14 Short
Challenge Level
The diagonal of a unit square is used as one of the sides of a new square.
What is the area of this new square?


(A unit square is a square whose sides all have length 1 unit, and so its area is 1 square unit)


This problem is taken from the World Mathematics Championships
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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