Calculate the radius and the area of the brick region?

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2 Answers
Apr 26, 2016

This problem is a whole lot simpler than the last one!

Explanation:

I'll assume that the circle touches both the top and the bottom of your figure perfectly...

Your diameter will be 30 cm (the height of your figure). Therefore, the radius measures 15 cm.

The formula for area of a circle is a= r^2pia=r2π

a = 15^2pia=152π

a = 225pia=225π

The area of the shaded region is 225π square centimetres.

Hopefully this helps!

p.s. where do you get your diagrams?

Apr 26, 2016

I just realized that your question on the top of the page contradicts your question on the diagram. Here is the answer to the question on the top

Explanation:

We must subtract the area of the circle.

A_(figure) = 30 xx 80

A_(figure) = 2400 square centimetres

A_(bricks) = 2400 - 225pi or 1693.14 square centimetres.

**Practice exercises:
The problems in the following pages can be done when you choose. Some of these images were not prepared by me, so please don't use them without my written consent.
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Hopefully this helps!