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Summing Consecutive Numbers

Age 11 to 14
Challenge Level Yellow star
Secondary curriculum
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Start by trying some simple cases; perhaps start by exploring what happens when you add two or three consecutive numbers.


$1 + 2 + 3 = 6$

$2 + 3 + 4 = 9$

Can you explain why the total has gone up by $3$?
 


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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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