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Bipin's Choice

Age 7 to 11
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Bipin is playing in a game show. The host tells Bipin that there are 10 balls hidden in a box - 5 are Red, 3 are Yellow and 2 are Blue. Bipin pulls out his first ball. It's Red and he wins a large sum of money. Now his choices are:

  1. He can stop playing and take his prize.
  2. He can pull out another ball - if it's Red he doubles his money, if it's Yellow he leaves with nothing, if it's Blue he can pick one last ball.
Bipin's Choice

What should Bipin do? Why?

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Roll These Dice

Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possible answers?

Trick or Treat

Mrs. Smith had emptied packets of chocolate-covered mice, plastic frogs and gummi-worms into a cauldron for treats. What treat is Trixie most likely to pick out?

A Bit of a Dicey Problem

When you throw two regular, six-faced dice you have more chance of getting one particular result than any other. What result would that be? Why is this?

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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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