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Weekly Problem 47 - 2011

Challenge Level: Challenge Level:1

Each pentagon has a turn of 36o to pack against its neighbour.

Therefore it will take 10 (x36o) turns to complete a full-turn, i.e. 10 pentagons

Therefore 7 more pentagons are needed.

chain of 10 pentagons around a circle

This problem is taken from the UKMT Mathematical Challenges.

View the previous week's solution