erikvm wrote:

Is the number of copies of a certain manuscript that n machines of type A can make in one hour greater than the number of copies of the manuscript that k machines of type B can make in one hour?

(1) \(n > k\)

(2) The number of copies of the manuscript that n machines of type A can make in one hour is 20

We need to determine whether the number of copies of a certain manuscript that n machines of type A can make in one hour is greater than the number of copies of the manuscript that k machines of type B can make in one hour.

If we let the rate of a type A machine = a and the rate of a type B machine = b, then the work done by n machines of type A in an hour is na and the work done by k machines of type B is kb. Thus, we need to determine:

na > kb ?

Statement One Alone:

n > k

Although we know that n is greater than k, without knowing the relationship between a and b, statement one is not sufficient to answer the question.

Statement Two Alone:

The number of copies of the manuscript that n machines of type A can make in one hour is 20.

Although we know that na = 20, we still do not know anything about k or b, thus statement two alone is not sufficient to answer the question.

Statements One and Two Together:

Using the information from statements one and two, we still do not have enough information to answer the question. We know that na = 20 and that n > k, however, we do not have any information about b.

Answer: E

_________________

Jeffery Miller

Head of GMAT Instruction

GMAT Quant Self-Study Course

500+ lessons 3000+ practice problems 800+ HD solutions