Question

Two containers designed to hold water are side by side, both in the shape of a cylinder. Container A has a diameter of 14 feet and a height of 9 feet. Container B has a diameter of 10 feet and a height of 20 feet. Container A is full of water and the water is pumped into Container B until Container A is empty. To the nearest tenth, what is the percent of Container B that is empty after the pumping is complete?

Answer 1

11.8 % empty

Explanation:

volume of cylinder : pi × r² × h

attention ! the question gives us diameter, so for radius we need to cut them in half.

Va = pi × (14/2)² × 9 = pi×49×9 = 1385.44236... ft³

Vb = pi × (10/2)² × 20 = pi×25×20 = 1570.79633... ft³

after filling B with everything in A there is still some empty volume in B

Vb empty = Vb - Va = 185.35397... ft³

so,

100% Vb = 1570.79633... ft³

1% Vb = 15.7079633... ft³

so, how often does 1% of the total volume of B fit into the remaining empty volume of B ?

185.35397... / 15.7079633... = 11.8%