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Percentage Unchanged

Age 14 to 16
ShortChallenge Level Yellow starYellow star
Secondary curriculum
  • Problem
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If the base of a rectangle is increased by 10% and the area is unchanged, by what percentage (exactly) is the width decreased by ?




You can find more short problems, arranged by curriculum topic, in our short problems collection.

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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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