Question

find the perimeter of semicircle whose radius is9 cm

Answer 1

perimeter of semicircle = half circumference = pi r
perimeter of semicircle = pi r + diameter
                                     = (3.14 x 9) + 18
                                     = 28.26 + 18
                                     = 46.26 cm

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Answer 2

Radius = 9cm

Diameter = 18cm

perimeter of semicircle = π × R + diameter

= 3.14 × 9 + 18

= 42.26

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