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Racing Odds

Age 11 to 14
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions


An elephant, a hippopotamus and a rhinoceros are entered for a race. The odds for the rhinoceros and the hippopotamus are:
2 to 1 against the rhinoceros winning and

3 to 2 against the hippopotamus winning.

What are the odds against the elephant winning if the race?

Editor's note: The hint explains 2 to 1 against in fractional form

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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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