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Unlocking the Case

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
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Asma and Atif were sorting through some things that had been brought in for the school jumble sale when they found an old case with a combination lock on it.

They had no idea what was in it but it was quite heavy and they wanted to find out what was inside. The only clue they had was a sticker next to the lock which said T16 and that there were three digits to find. What did the code mean? What was the combination that unlocked the case?

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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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