Copyright © University of Cambridge. All rights reserved.

## 'One or Both' printed from http://nrich.maths.org/

An ideal opportunity to discuss different approaches to a solution
which might result from students working on the first part of the
problem.

Out of the methods adopted by the students might emerge the idea
that the pupils in the problem who got both questions correct have
been counted twice so 9 must represent any percentage over 100.
This might be a useful idea when trying to tackle the second part
of the problem.

The third part of the problem aims at encouraging greater
generalisation and therefore reinforce some of the ideas developed
in the first part of the problem.