The three examples below give a feel for the range of solutions we received. They are interesting in their range of approaches and detail. Well done to all of you.

Firstly, Rachael and Katy of Ardingly College Junior School who sent a solution obtained through trial and improvement. Some people undervalue this valid mathematical method and it can often lead us to a very complete answer or, at the very least, throw light on what to be looking for when finding a fuller solution to the problem.

James sent us this solution

A very complete solution, which explains the equality of the three unknowns more fully was supplied by Derek of Tin College.