If m ≠ 1 and if nm/(n - m) = 1, what is the value of n in terms of m?
Choose one:  A) m/(m+1)  B) (m - 1)/m  C) m/(1-m)  D) (m + 1)/m  E) (1 - m)/m
This question comes with a particular 'quirk' (one that you probably won't see on Test Day). The GMAT won't test you on the concept of undefined numbers (re: numbers divided by 0), so any time that this concept is a possibility, the question writers have to add a restriction that removes the option that a 0 could occur in the denominator.   Here, we're told that B CANNOT = 1, which is a bit strange because that restriction doesn't seem to impact the original equation much. In fact, it impacts JUST ONE of the answer choices - so you have to ask WHY that restriction is even there. It's actually because that one answer is the correct one.   Final Answer:   m/(1-m)
<result>C</result>
If m ≠ 1 and if nm/(n - m) = 1, what is the value of n in terms of m?