AAPL wrote:Madge paid A dollars for R bananas. Dean paid B dollars for S bananas. Which one of them paid a higher price-per-banana?
1) B > A
2) R > S

Given: Madge paid A dollars for R bananas. Dean paid B dollars for S bananas.

Target question: Which one of them paid a higher price-per-banana?

Statement 1: B > A
This tells us that Dean PAID more than Madge paid.
However, we don't know HOW MANY bananas each person bought.
Consider these two conflicting cases:
Case a: Dean paid $10 for 2 bananas, and Madge paid $6 for 3 bananas. In this case, the answer to the target question is Dean paid a higher price per banana
Case b: Dean paid $10 for 10 bananas, and Madge paid $6 for 3 bananas. In this case, the answer to the target question is Madge paid a higher price per banana
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: R > S
This tells us that Madge bought more bananas that Dean bought.
However, we don't know the amount that each person PAID
Consider these two conflicting cases:
Case a: Dean paid $10 for 2 bananas, and Madge paid $6 for 3 bananas. In this case, the answer to the target question is Dean paid a higher price per banana
Case b: Dean paid $2 for 2 bananas, and Madge paid $6 for 3 bananas. In this case, the answer to the target question is Madge paid a higher price per banana
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
The combined statements tell us that Dean PAID more than Madge, and that Dean bought fewer bananas than Madge bought.
If Dean paid more money to get fewer bananas, then Dean definitely paid more per banana.
So, the answer to the target question is Dean paid a higher price per banana
Since we can answer the target question with certainty, the combined statements are SUFFICIENT

Answer: C

Cheers,
Brent