Climbing Ropes
Age 14 to 16
ShortChallenge Level 
Climbers use ropes of different diameters.
A 50 m rope which is 9 mm in diameter weighs about 2.7kg.
Roughly what would a 100 m rope of the same material, but of diameter 11 mm weigh?
This problem is taken from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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