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'Red Balloons, Blue Balloons' printed from https://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.