Bunuel wrote:

What is the volume, in cubic meters, of the water in a certain rectangular tank, if the constant depth of the water is 1/3 feet?

(1) The base of the rectangular tank is 6 feet wide and 8 feet long.

(2) If water is drained from the tank until the depth of the remaining water is 1/4 feet, the volume of the drained water is 4 cubic feet.

As we know the height, all we need to know is the area of the base.

We'll look for statements that give us this information, a Logical approach.

(1) exactly what we need!

Sufficient!

(2) this tells us that a specific fraction of the volume, 1 - (1/4)/(1/3) = 1 - 3/4 = 1/4, is 4 cubic feet. Then we calculate the total volume. (note that we didn't actually have to calculate the fraction, just to notice that we could have)

Sufficient.

(D) is our answer.

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