Copyright © University of Cambridge. All rights reserved.
'Round Trip' printed from https://nrich.maths.org/
I walk to the bike shop at 3 miles per hour, and I cycle home at 12 miles per hour. What is my average speed, in miles per hour, for the time that I am actually on the route?
If you liked this problem,
here is an NRICH task which challenges you to use similar mathematical ideas.