Question

Can you tell me the APPROXIMATE perimeter?

Answer 1

Oh yikes. I haven't done geometry in forever, so bear with me.

We obviously have a rectangle and then two half-circles, so we need to find the perimeters and areas of them separately.

15 is the diameter for the larger circle (meaning the radius is 7.5), and 6 is the diameter for the smaller circle (meaning the radius is 3).

The perimeter for a circle is diameter times pi. The area of a circle is pi times radius squared. The perimeter of a rectangle is 2 times the length plus 2 times the width. The area of a rectangle is the length times the width.

If you apply these formulas with the values you're given, you can easily approximate the numbers. Don't forget, you're dealing with HALF circles, not whole ones, so be sure to divide your circle answers by 2.

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Of course, if you want to be really vague (approximate how generally??), you can just eyeball it. 15 times 6 is 90, so the area of the rectangle is 90, and the larger circle looks to be about one-and-a-half times the size of the rectangle. If I were to guess just based on looking at it, I would say 180 is a nice guess. But once again, you may want to go through this more precisely.

I'm not working it out for you, but this should get you off on the right foot. Have fun (: