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Almost One

Age 11 to 14
Challenge Level Yellow star
Secondary curriculum
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Almost One printable sheet


Here is a set of six fractions: $$\frac{1}{6} \quad \frac{1}{25} \quad \frac{3}{5} \quad \frac{3}{20} \quad \frac{4}{15} \quad \frac{5}{8} $$

Choose some of the fractions and add them together. You can use as many fractions as you like, but you can only use each fraction once.
Can you get an answer that is close to 1?
What is the closest to 1 that you can get?




With thanks to Colin Foster who introduced us to this problem.




 

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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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