Question

A circle has an area of 2254 square inches. If the radius of the circle

is multiplied by 6, then what is the area of the new circle formed?
O A) 1000+ in.2
OB) 2270n in.
OC) 68057 in.2
OD 81007 in.2

Answer 1

Answer: OD 81007 in.2

Explanation:

Use formula for area of circle, which is A = πr²

The radius is squared, so if the radius or a new circle is 6 times larger (multiplied by 6), the difference in area will be 36 times greater. So the area is

225π(36) = 8,100π

Answer 2

D)
`8100\pi` in²

Explanation:

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Question:

A circle has an area of 225
`\pi` square inches. If the radius of the circle is multiplied by 6, then what is the area of the new circle?

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area of a circle =
`\pi r^2` (where r is the radius)

⇒
`\pi r^2=225\pi` in²

If the radius is multiplied by 6, then r = 6r

⇒ area =
`\pi (6r)^2=36\pi r^2`

Therefore, if
`\pi r^2=225\pi`

then
`36\pi r^2 = 36 * 225\pi =8100\pi`