A van moves 50 miles with a constant speed of 20 mph and another 84 miles with a constant speed of 56 mph. How much time in total does it take to travel these distances?

A) 1 hour

B) 4 hours

C) 1.5 hours

D) 2.5 hours

B) 4 hours

Explanation:

the equation relating speed, distance and time is as follows

speed = distance / time taken

the van moves 50 miles at 20 mph and the next 84 miles at 56 mph

so lets calculate the time taken at both speeds

substituting the values in the above equation

20 mph = 50 miles / time

time taken = 50 / 20 = 2.5 hours

56 mph = 84 miles / time

time taken = 1.5 hours

the totat time taken is - 2.5 + 1.5 = 4 hours