NRICH - An Unhappy End

Speed
Key Stage: 3 ★★

Two engines are travelling towards each other on a single track railway line. A fly starts on one engine and flies towards the other engine, turning at each engine. How far does the fly travel before the unhappy end?

This problem only requires some simple understanding of the relationship between time, distance and speed, but it will require clear thinking and insight to solve. It provides a good experience of the mathematical 'lightbulb' moment when a seemingly tricky problem is solved using a clever trick or alternative viewpoint.

This resource has comprehensive teachers' notes and resources, linked from the problem page. This includes possible approaches and key questions, as well as possible support and extensions.


The file attached is a HTML file, which, when opened, automatically redirects you to the problem on the NRICH website.