Maths Olympiad Prep

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UKMT Hamilton Olympiad, 2017

Combinatorics Difficulty 3.0 AMC 10/12 Prove it United Kingdom

A ladybird walks from AA to BB along the edges of the network shown. She never walks along the same edge twice. However, she may pass through the same point more than once, though she stops the first time she reaches BB. How many different routes can she take?

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