a question from the official guide for gmat review (12th edition) diagnostic test.
A closed cylindrical tank contains 36pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the height, in feet, of the surface of the water above the ground?
(A) 2
(B) 3
(C) 4
(D) 6
(E) 9
the answer is B.
according to the answer key, they got this answer by...
V = (pi)(r^2)(h) <----formula for volume of cylinder
36pi = (pi)(r^2)(h) <-----just input the values given
solve for r and that's the answer.
my question is....if the tank was only filled to HALF of its capacity, why didn't the answer key divide the 36pi in half?
shouldn't the thought process be ...
(36pi)/2 = (pi)(r^2)(h)
A closed cylindrical tank contains 36pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the height, in feet, of the surface of the water above the ground?
(A) 2
(B) 3
(C) 4
(D) 6
(E) 9
the answer is B.
according to the answer key, they got this answer by...
V = (pi)(r^2)(h) <----formula for volume of cylinder
36pi = (pi)(r^2)(h) <-----just input the values given
solve for r and that's the answer.
my question is....if the tank was only filled to HALF of its capacity, why didn't the answer key divide the 36pi in half?
shouldn't the thought process be ...
(36pi)/2 = (pi)(r^2)(h)
