GMAT Problem Solving (PS) | Re: The inside dimensions of a rectangular wooden box are 6

Found this useful tip to be remembered as a thumb rule in another post .

As a rule of thumb, in such problems, select the second largest side as the diameter (note that it is the diameter and one has to calculate the radius by dividing by 2 before calculating the volume). And the left alone smallest side will be the height of the cylinder (as you need the two largest sides to enclose the bottom of the cylinder the only choice left out for height is the smallest side).

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