Copyright © University of Cambridge. All rights reserved.

A van travels from Newcastle to South Shields at an average speed of 30 mph and returns by the same route at an average speed of 40 mph. What is the van's average speed for the whole journey?

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

*This problem is taken from the UKMT Mathematical Challenges.**View the archive of all weekly problems grouped by curriculum topic*