Question

A 540-mile, 10 hour trip was driven in two legs. For the first leg of the trip, the average speed was 65 mph. Then the traffic increased, and the remainder of the trip was driven at an average speed of 50 mph. For how long was the car driven at each speed?

A) 6 hours at 65 mph and 4 hours at 50 mph
B) 5 hours at 65 mph and 5 hours at 50 mph
C) 7 hours at 65 mph and 3 hours at 50 mph
D) 8 hours at 65 mph and 2 hours at 50 mph

Answer 1

The car was driven for A) 6 hours at 65mph and 4 hours at 50mph. Hence, A) is correct.

Step-by-step explanation:

To find out how long the car was driven at each speed, we can solve the problem using the formula:

Average Speed = Total Distance / Total Time

Given that the total distance of the trip is 540 miles and the total time is 10 hours, we can set up the following equation:

65mph * t1 + 50mph * t2 = 540,

where t1 and t2 are the times (in hours) spent driving at each speed.

We also know that t1 + t2 = 10, since the total time is 10 hours.

Solving this system of equations, we find that t1 = 6 and t2 = 4.

Therefore, the car was driven for 6 hours at 65mph and 4 hours at 50mph.