Question

If the diameter of a cemicircular protector is 14cm then find it's perimeter

Answer 1

Given that the diameter of semicircular
protector = 14 cm

since , we know that diameter of semicircle

= 2 r

here,diameter of semicircular protector = 14 cm

2 r = 14

r = 7 cm
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since we know that perimeter of semicircle=circumferenceof semicircle = πr + 2r
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so now

perimeter of semicircular protector

= π r + 2r

= 22 × 7 / 7 + 2 × 7

= 22 + 14 = 36 cm

therefore ,

perimeter of semicircular protector = 36 cm

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Your Answer : perimeter = 36 cm
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Answer 2

Find the radius:

Radius = Diameter ÷ 2

Radius = 14 ÷ 2 = 7 cm

Find the circumference of the circle:

Circumference = 2πr

Circumference = 2π (7) = 44 cm

Find the circumference of the semicircle:

Circle = 44 cm

semicircle = 44 ÷ 2 = 22 cm

Find the perimeter:

Perimeter = 22 + 7 + 7 = 36 cm

Answer: The perimeter is 36 cm