Hello,
The two questions below I cannot agree with GMAT's answers. Can anyone explain how their answers are correct?

Here I believe the answer is 25, GMAT says it is 20. My logic is as follows:
The cyclist at 20mph got 1.666 miles in 5 mins (5mins is 1/12th of an hour --> 20/12 = 1.666). The hiker went a mile every 15 minutes (a third of a mile every 5 mins). Therefore, it took the hiker 15 mins to do the first mile, and 10 mins to do the next 2/3's of the distance. 15+10 =25, not 20. Is my logic flawed?

I believe both statements are insufficent, GMAT says it is solveable with both. My logic is as follows: Statement 2 says X > Y. Therefore, we can plug #'s into statement one.
First I used X =3, Y=2.5 --> 2(3)-2(2.5) ---> 6-5 =1, X and Y positive work.
Now lets try some negative numbers. X=-2, Y=-2.5 ---> 2(-2) - 2(-2.5) ---> -4 +5 = 1
We can solve it with both x and y positive, and x and y negative, therefore we dont know if x and y are both positive.... I said E, they say C.
Thanks,
-Dave[/img]
The two questions below I cannot agree with GMAT's answers. Can anyone explain how their answers are correct?

Here I believe the answer is 25, GMAT says it is 20. My logic is as follows:
The cyclist at 20mph got 1.666 miles in 5 mins (5mins is 1/12th of an hour --> 20/12 = 1.666). The hiker went a mile every 15 minutes (a third of a mile every 5 mins). Therefore, it took the hiker 15 mins to do the first mile, and 10 mins to do the next 2/3's of the distance. 15+10 =25, not 20. Is my logic flawed?

I believe both statements are insufficent, GMAT says it is solveable with both. My logic is as follows: Statement 2 says X > Y. Therefore, we can plug #'s into statement one.
First I used X =3, Y=2.5 --> 2(3)-2(2.5) ---> 6-5 =1, X and Y positive work.
Now lets try some negative numbers. X=-2, Y=-2.5 ---> 2(-2) - 2(-2.5) ---> -4 +5 = 1
We can solve it with both x and y positive, and x and y negative, therefore we dont know if x and y are both positive.... I said E, they say C.
Thanks,
-Dave[/img]












