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Dopey Measurement

Age 14 to 16
ShortChallenge Level Yellow starYellow star
Secondary curriculum
  • Problem
  • Solutions


Snow White wanted to know the mean height of the Seven Dwarfs, so one day she measured them all as they left for work.

She calculated their mean height as 112.3 cm.

Doc complained that she had left him out and measured Dopey twice without him noticing.

If Doc is 3.5 cm taller than Dopey, what is the mean height of the Seven Dwarfs?

 

This problem is taken from the UKMT Mathematical Challenges.
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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