Thank you for this explanation. I'm still not fully convinced of the reasoning of why this is the best answer... one pen might cost more than five pencils, but five pencils is not five pens. I am still inclined to think that either a or d could be deemed appropriate. But now I understand better why d would make sense.
Just found this forum because I'm helping a friend practice for this test. For the first problem: I doubt this question is still part of the test but a search around the internet indicates the answer apparently D) peter has enough money to buy pencils, but not enough money to buy pens Personally, I don't see how this is the most appropriate answer (for me that's A) can anyone from this previous discussion help by finding a way to justify that it is D?