So, if Peter doesn't have enough to buy 5 pens, the most appropriate answer (to me) is (A) that Peter has enough to buy 1 pen.
This is because all the other answers we cannot answer DEFINITELY because we do not know the cost of the other items, we just know the relative cost to pens. They may not even be a reasonable price relative to pens, so we cannot judge how much Peter can afford unless the amount is cheaper than 5 pens. It seems to me to be less about math and more about reasoning and reading the question verbatim. Don't overthink it. It's silly, but I believe the nature of the test is to see how well you think it out. Let's go through each answer and reason it out.
A.) Peter has money to buy 1 pen. YES. If Peter doesn't have enough to buy 5 pens, then he obviously has enough to buy 4 pens or less. So he has enough to buy 1.
B.) Peter does not have money to buy 1 pen. NO. The statement just said Peter does not have money to buy 5 pens. So this is incorrect. He just doesn't have enough for 5 pens. Anything less than 5 pens is okay.
C.) Peter has enough to buy 5 pencils. Probably, but not sure. Pens could cost $5 each and pencils could cost $4.99. In that case, 5 pens are $25 even and 5 pencils are $24.95. If Peter has $24.97, he cannot afford 5 pens or 5 pencils. If I saw Peter in this predicament, I would just give him the $0.05, so we can end this misery, but apparently there isn't anyone willing to do that right now.
D.) Peter has enough money to buy pencils, but not enough money to buy pens. Again, like answer C this is probably true, but it is not able to be determined with the information given. It is possible to not be able to afford pens and not afford pencils at the same time. Notice they didn't say 1 pen or 1 pencil, they say pencils (with an "s"). That could mean 10 pencils, 50 pencils, who knows?
E.) Peter has enough to buy erasers. What? Where did erasers come from? He can't even afford 5 pens! If erasers are more expensive, we can't be sure he can afford them. If 5 pens = $25, and 1 eraser = $25, they still fulfill the limits on the statement and he can't afford it. No Peter!! Just no.
For the second question Dayan in the previous post nailed it. It's exactly how he explained it. It helps to count out the order of each variable which was my first inclination when you see things in a random (letters, numbers, symbols, etc) pattern like this. Another type of question is If they were all numbers, think about counting the amount between the numbers, like, 1,3,5,7 are 2 apart. You can sometimes see a pattern there or increments. Always try to find a pattern. There is always a pattern.
I find this years later, but I hope this helps someone one day!
- HootersGeek