Copyright © University of Cambridge. All rights reserved.

A roll of adhesive tape is wound round a central cylindrical core
of radius $3 \; \text{cm}$. The outer radius of a roll containing
$20 \; \text{m}$ of tape is $4 \; \text{cm}$. What is the outer
radius of a roll containing $80 \; \text{m}$ of tape?

View the current weekly problem

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

View the current weekly problem