ferpape wrote:
Peter and Tom shared the driving on a certain trip. If Peter and Tom both drove for the same amount of time, but Peter only drove 2/5 of the total distance, what was the ratio of Peter's average speed to Tom's average speed?
1)1:5
2)2:5
3)1:2
4)3:5
5)2:3
We can let the time driven by Peter and Tom = t. If we let the total distance = d, then Peter's distance = (2/5)d = 2d/5 and Tom's distance = (3/5)d = 3d/5.
Thus, Peter's rate is (2d/5)/t = 2d/5t and Tom's rate is (3d/5)/t = 3d/5t.
The ratio of Peter's average speed to Tom's average speed is (2d/5t)/(3d/5t) = 10dt/15dt = 2/3.
Answer:
E
