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15.
Can someone help me?​

15. Can someone help me?​-example-1
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1 Answer

12 votes

Answer:

The radius, in inches, of the base of the cone will be:

r = 6 inches

Hence, option B is correct.

Explanation:

Given

The Volume of a right circular cone V = 24 π cubic inches

The height of the cone h = 2 inches

To determine

The radius of the base of the cone r = ?

Using the formula involving Volume m, height h, and radius r of a right circular cone.


V\:=(1)/(3)h\:\pi \:\:r^2\:

substituting V = 24 π, h = 2 to find the radius r


\left(24\pi \right)=(1)/(3)\left(2\right)\:\pi \:r^2

switch sides


(1)/(3)\left(2\right)\pi r^2=\left(24\pi \right)


(1)/(3)2\pi r^2=24\pi

simplify


2\pi r^2=72\pi

Divide both sides by 2π


(2\pi r^2)/(2\pi )=(72\pi )/(2\pi )


r^2=36


\mathrm{For\:}x^2=f\left(a\right)\mathrm{\:the\:solutions\:are\:}x=√(f\left(a\right)),\:\:-√(f\left(a\right))


r=√(36),\:r=-√(36)

Thus,


r=6,\:r=-6

As we know that the radius can not be negative.

Therefore, the radius, in inches, of the base of the cone will be:

  • r = 6 inches

Hence, option B is correct.