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The circle of radius 4cm is divided into four congruent parts by arcs of radius 2cm as shown.
What is the length of the perimeter of one of the parts, in cm?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Four Parts
Age 14 to 16
ShortChallenge Level 
The circle of radius 4cm is divided into four congruent parts by arcs of radius 2cm as shown.What is the length of the perimeter of one of the parts, in cm?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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