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## 'Bipin's Choice' printed from http://nrich.maths.org/

### Why do this
problem?

Probability is a difficult concept and questions such as

this, which invites discussion, can help children to get to
grips with the difference between a calculated result (theoretical
probability) and what actually happens (experimental probability).
Playing the game with a bag full of coloured balls can help to make
the link.

### Key questions

The first ball taken out is a red one, how many balls of each
colour are left?

What is the chance of picking another red ball?

What is the chance of of picking a yellow ball?

If you had won some money and could lose it by playing again,
would you stop playing? Why?

### Possible extension

Make up a similar question with different numbers of coloured
balls. Are there any combinations of colours that would make it
clear what to do? Why?

### Possible support

Playing the game with a bag full of coloured balls and
discussing the possible outcomes can help to make the link. Talk is
really important in understanding probability.