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Consecutive Numbers

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Have You Got It?

Can you explain the strategy for winning this game with any target?

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Pair Sums

Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

Multiplication Mistake

Age 11 to 14 Short Challenge Level:

Jane made a mistake when writing down a multiplication, and she multiplied by 54 instead of 45. Her answer was 198 too big. What number did she multiply 54 by?


This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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.
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NRICH is part of the family of activities in the Millennium Mathematics Project.