Question

In the morning, Margret drove to a business appointment at 50 mph. Her average speed on the return trip in the afternoon was 40 mph. The return trip took (1/4) hours longer because of heavy traffic. How far did she travel to the appointment? ...?

Answer 1

Distance equation is: distance = speed * time
t = time to the appointment
(t+0.25) = time back from the appointment (0.25 = 1/4)

50t = 40(t+0.25)
50t = 40t + 10
50t - 40t = 10
10t = 10
t = 1 hour
So, it took her one hour to get to the appointment, which means that the distance will be 50 miles, since she traveled 50 mph, which is 50 miles, since the time is one hour.