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Age 11 to 14 Short Challenge Level:

Clare has some yellow square tiles and 62 green square tiles (which are all the same size). She makes a rectangle with yellow tiles on the inside and green tiles completely around the perimeter.

What is the largest possible number of yellow tiles in the pattern?


This problem is adapted 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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