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Backwards Laps

Age 14 to 16
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Secondary curriculum
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Chris and Sophie are running in opposite directions around a track, with constant speeds. Chris notices that he passes Sophie every 24 seconds.

It takes Chris 60 seconds to complete each lap.

How long does it take Sophie to complete each lap?


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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