Copyright © University of Cambridge. All rights reserved.

'Circle Time' printed from https://nrich.maths.org/

Show menu


Three circles $C_1$, $C_2$ and $C_3$, of radii 1 cm, 2 cm and 3 cm respectively touch as shown. $C_1$ meets $C_2$ at $P$ and meets $C_3$ at $Q$.

What is the length in cm of the longer arc of circle $C_1$ between $P$ and $Q$?

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.
You can find more short problems, arranged by curriculum topic, in our short problems collection.