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Find the perimeter. All curves shown are semicircles. (use 3.14 for )

Find the perimeter. All curves shown are semicircles. (use 3.14 for )-example-1
User Coryrwest
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1 Answer

18 votes
18 votes

Perimeter of curved shape = 38.644m

Step-by-step explanation:

To find the perimeter of the curve, we would sum all the sides in the curve.

The other straight sides are known. Let's find the curved part.

We would apply perimeter of a semicircle since the curve is half of a circle.

Perimeter of a semicircle = πr + diameter

diameter of the curve = 9.2m

diamter = 2(radius)

radius = r = diamter/2

r = 9.2/2 = 4.6m

π = 3.14

Perimeter of a semicircle = (3.14 × 4.6) + 9.2 = 14.444 + 9.2

Perimeter of a semicircle = 23.644

Note that the curve part is open. This means the straight line on the semicircle is missing.

This straight line is the diameter.

So we need to remove the diamter from the perimeter of the semicircle

The length of the curved part = perimeter of the semicircle - diameter

The length of the curved part = 23.644 - 9.2 = 14.444m

Now we find the curved shape = length of the base + the two vertical sides + the length of the curved part

length of the base= 9.2m, vertical sides = 7.5m

Perimteter of curved shape = 9.2m + 2(7.5m) + 14.444m

Perimteter of curved shape = 38.644m

User Jarred Parr
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