Let the time taken be t, and the distance be d.

Then condition 1. tells us that::

d/t=72.

Note enough information as it stands to find t.

Condition 2. tells us that the same distance can be covered in 1 hour less time at 80 miles per hour so:

d/(t-1)=80

or

d=80t-80

Not enough information in this to find t, but with the previous equation we

have a pair of simultaneaou equations which will allow us to find both d and t.

from the first equation d=72t. Substitute this into the second:

72t=80t-80

rearranging:

8t=80,

or t=10 hours

RonLThe multiple choice answers are (it's a GMAT problem):

A. Statement 1 is enough, but not statement 2.

B. Statement 2 is enough, but not statement 1.

C. Both Statement 1 and 2 are needed to answer this question.

D. Either statement can be used to answer this question.

E. Neither statement can be used to answer this question.

I chose E, but this exam says that the answer is C. I just don't see how this can be solved without a total distance and a time.

Thanks in advance.