Question

Hey!!! Maths genius ??

If the perimeter of a semicircle is 18cm, what will be it's diameter

With Steps

Answer 1

hello friend ... here is your answer just below.

$perimeter \: of \: semi \: circle = \pi \: r \\ 18 = \frac{22}{7} \times r \\ \\18 \times 7 = 22r \\ \\ 5.7 = r \\ diameter = 2r \\ 5.7 \times 2 = 11.4cm \: is \: the \: answer$
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Answer 2

Answer:

7 cm

Step-by-step explanation:

Given, Perimeter of semi-circle = 18 cm.

We know that Perimeter of semicircle = Diameter + πr

⇒ 18 = 2r + πr

⇒ 18 = r(2 + π)

⇒ 18 = r(2 + 22/7)

⇒ 18 = r(36/7)

⇒ 126 = 36r

⇒ r = 3.5 cm.

We know that Diameter = 2r = 7 cm.

Hope it helps!