Question 306570
William drove 5 hours at the average speed of 54 miles an hour. For the first 2 hours, he drove 45 miles an hour. What was his average for the last 3 hours?

time driven = 5 hours

54 miles / hour

Distance traveled = 54 * 5= 270 miles

2 hours @ 45 mph

distance traveled = 90 miles

270-90= 180 miles is the second leg distance 

180/3 = 60 mph
Next 3 hours he drove at 60 mph