Answered

The volume of a cone varies jointly with its height and the square of its base radius. A cone has a base radius of 4ft, height of 6 ft, and volume 100.48(cubed feet).

What is volume of a cone with a height of 3ft, and a base radius of 3ft.

Answer :

"Joint variation" means "directly, but with two or more variables". We calculate as follows:

Volume = khr^2
100.48 =  k (6)(4^2)
k = 1.05

Volume = 1.05h(r^2)
Volume = 1.05(3)(3^2)
Volume = 28.35 ft^3

Answer: Letter C

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