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## 'Red Balloons, Blue Balloons' printed from http://nrich.maths.org/

### Why do this
problem?

This problem would be a good one when doing calculations with
fractions. It also requires logical thinking and organising of
results. Different strategies and approaches can be taken:
knowledge of addition, or multiples, or an
understanding of fractions can be used to arrive at a
solution.

### Key questions

What do you think is a good way to start?

How big was Katie's balloon after the second (third, fourth
etc.) puff?

How big was Will's balloon after the second (third, fourth
etc.) puff?

### Possible extension

Learners could make up a similar problem of their own for a friend
to try.

### Possible support

Breaking the problem down step by step will help learners reach a
solution. It might be useful to have each subsequent
piece of information written on a separate card so that they can be
given to children when ready, rather than presenting all the
information at once.