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Pattern of Islands
Age
11 to 14
Challenge Level
Problem
Getting Started
The council has decided to build bridges linking the islands Ander, Bresh, Calo, Daple and Ellip.
They want to make sure that
there will be two bridges leading from each of the islands Ander, Bresh and Calo, and three leading from Ellip and Daple
no pair of islands will be joined by more that one bridge
How many different ways are there to do this?