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3 votes
3 votes
I don't understand how to do this

I don't understand how to do this-example-1
User Mmeyer
by
2.5k points

1 Answer

9 votes
9 votes

Answer:

64
\pi in²

Explanation:

I did not ever do a problem like this, however this is the beauty of math, you can easily reverse engineer it.

Remember,

A =
\pi
r^(2)

And if we have 4 circles that means the area of one circle is 1/4th the total

So,

A=
(\pi r^(2) )/(4)

Assuming that 16 is the radius squared times 4 lets ignore that squared for now because when going backwards we would get rid of the squared last as that was the first step.

A=
(16\pi )/(4)=
(4\pi )/(1)=4
\pi

Now lets get it back to
r^(2) by square rooting the 4

A=
√(4\pi )=2
\pi

The radius of one small circle is 2. Therefore; the diameter would be 4 for each. This in mind we know that two small circles diameters make up the radius of the larger circle we will multiply it by two again.

This gives us a final radius of the bigger circle of 8

Therefore, the area of the bigger circle is 8²
\pi which simplifies to 64
\pi

And a final answer of

64
\pi in²

Hope this helps :)

User Harsh
by
3.2k points