Did you solve it? Are you in the smartest 10%?
by Alex Bellos from on (#2RXSB)
The answer - with workings! - of the puzzle that stumped nine out of ten 18-year-olds around the world.
In this blog earlier today I set you this puzzle:
A string is wound symmetrically around a circular rod. The string goes exactly four times around the rod. The circumference of the rod is 4cm and its length is 12cm. Find the length of the string.
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