Data Sufficiency

Who types at a faster rate, John or Bob?
(1) The difference between their typing rates is 10 words per minute.
(2) Bob types at a constant rate of 80 words per minute.

Answ: E

Initially, I thought the answer should be C

Bob's rate = 80 w/m
Difference = Bob's rate - John's rate

10 = 80 - J
J = 70

Any ideas?

Thanks!

oks,

You are assuming from (2) that Bob's rate of 80 w/m is greater than John's. For all we know, John could type at a rate of 90 w/m OR 70 w/m like you thought.

oks,

You are assuming from (2) that Bob's rate of 80 w/m is greater than John's. For all we know, John could type at a rate of 90 w/m OR 70 w/m like you thought.