Question

A man travels from town x to town y at an average rate of 60 mph and returns at an average rate of 50 mph. He takes a 1/2 hour longer than he would take if he mage the round trip at an average of 55 mph. What is the distance from town x to town y

Answer 1

D/60 + D/50 = 2D/55 - 1/2

find common denominator ( 3300)

3300/60 = 55

3300/50 = 66

3300/55=60

so then you get 55D +66D= 60(2D)-1650

121D=120D-1650

D=1650 miles

check

1650/60 =27.5, 1650/50 = 33, 27.5 + 33 = 60.5 hours total

1650/55 = 30, 30 x 2 = 60

60.5-60 = 0.5 longer

so distance = 1650 miles