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Spell by Numbers

Age 7 to 11
Challenge Level Yellow starYellow star
  • Problem
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Can you substitute numbers for the letters in these sums?

tea cup hip joint. foot. father and son. pig. huts.

TEA+SEA=EAT, TOO+TIP=HIP, TOE+HO=THE, GOT+SUP=HUG, PIG+SO=PEG, HIT+TO=HUT.

Did you know? Mathematical problems in which you replace digits with letters that make words or even phrases are called CRYPTARITHMS.


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ABC

In the multiplication calculation, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?

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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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