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Upper primary school mathematics question UPQ104
Find the perimeter of a semicircle with radius 7 cm.
(Take π = 22/7)
The perimeter of a circle = 2 × π × r
Length of the semicircle arc = 2 × π × 7 ÷ 2 = 22/7 × 7 = 22cm
The perimeter of the above semicircle = 22 + 7 + 7
Need to remember that perimeter is a enclosure of a figure. Remember to add the length that closing the semicircle.