How many hours did it take Dale to drive from A-town to

[swerve]

How many hours did it take Dale to drive from A-town to B-town?

1) If Dale's average speed for the trip had been three times as fast, the trip would have taken 2 hours.
2) The distance from A-town to B-town is 100 miles.

The OA is A.

Please, can anyone explain this DS question? I tried to solve it but I'm not sure. I need help. Thanks.

[GMATGuruNY]

How many hours did it take Dale to drive from A-town to B-town?

1) If Dale's average speed for the trip had been three times as fast, the trip would have taken 2 hours.
2) The distance from A-town to B-town is 100 miles./quote]

Rate and time have a RECIPROCAL RELATIONSHIP.
1/2 AS FAST implies TWICE THE TIME.
1/5 OF THE TIME implies 5 TIMES AS FAST.

Statement 1:
3 times as fast implies 1/3 of the time.
Since 1/3 of the normal time is equal to 2 hours, we get:
(1/3)t = 2
t = 6 hours.
SUFFICIENT.

Statement 2:
Here, the time can be any positive value.
INSUFFICIENT.

The correct answer is A.