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There isn't an obvious way to rephrase this question. We can't cross-multiply because we don't know whether p is negative. (You could rephrase giving yourself a positive and negative case, but this can become confusing). The best thing to do it to try to PROVE INSUFFICIENCY when looking at the statements.
Question: Is (1/p) > r/(r^2 + 2) ?
1) p = r
Test values to prove insufficiency:
If p and r both equal 1: (1/1) > 1/(1^2 + 2) --> 1 > 1/3 yes.
If p and r both equal -1: (1/-1) > -1/((-1)^2 + 2) --> -1 > -1/3 no.
Insufficient.
2) r > 0
This tells us nothing about p. Insufficient.
1 & 2) Together, if r > 0 then p > 0. We only need to test positive values:
If p and r both equal 1: (1/1) > 1/(1^2 + 2) --> 1 > 1/3 yes.
If p and r both equal 2: (1/2) > 2/(2^2 + 2) --> 1/2 > 2/6 yes.
If p and r both equal 3: (1/3) > 3/(3^2 + 2) --> 1/3 > 3/11 yes.
Any positive value we test would give us a "yes" result. The answer is C.
