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The two right circular cylinders A and B above have diameters of 8 and 12 respectively. If the volume of B is twice the volume of A, what is the ratio of the height of A to the height of B?

The two right circular cylinders A and B above have diameters of 8 and 12 respectively-example-1
User Jsstuball
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1 Answer

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answer: (e) 9/8

the volume of a cylinder is 1/3(h)(r^2)(pi).

so, if we have x as the height of cylinder A and y as the height of cylinder B ...

volume cylinder A = (16/3)(x)(pi)

volume cylinder B = (36/3)(y)(pi)

and since volume B = 2 (volume A), if we plug in what we calculated, we have...

2(16/3)(x)(pi) = (36/3)(y)(pi)

(2)(16)x = 36y

32x=36y

8x = 9y

thus the answer is e, as if we plug in x = 9 and y = 8 into our equation, we get 72 = 72 which is true.

User Ronnie Jespersen
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