What is the perimeter of this shape |
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To answer this question, we need to realize that the figure is just half of a circle. This means we will still be using the formula . However, there will be a twist in what we do, because the formula
gives us the circumference of a complete circle.
You will solve this problem using three steps: find the circumference of a full circle with the same diameter, divide that circumference in half, and then add the diameter.
Example 1 What is the perimeter of this shape |
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Step 1: Find the circumference of the full circle. ![]() |
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Step 2: Divide the circumference in half. ![]() |
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Step 3: Add the diameter. 12.56 + 8 = 20.56 cm This is the perimeter of the semi-circle! |
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Example 2 Find the perimeter of this quarter circle. ![]() |
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Example 3 A wire is bent to form three semicircles. Find the length of the wire in terms of ![]() |
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Solve each of the following problems.
Find the perimeter of this shape. ![]() |
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Find the perimeter of this shape. ![]() |
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A garden is in the shape of a quarter circle. Find its perimeter. ![]() |
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A circle is drawn inside a square. Find the circumference of the circle. ![]() |
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![]() A rope is arranged to form two semi-circles as shown. Find the length of the rope in terms of ¹. |
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