SOLUTION: A car travels 20 kilometers per hour faster than a second car. The first car covers 180 kilometers in the same time the second car covers 135 kilometers. What is the average speed

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A car travels 20 kilometers per hour faster than a second car. The first car covers 180 kilometers in the same time the second car covers 135 kilometers. What is the average speed      Log On


   



Question 782000: A car travels 20 kilometers per hour faster than a second car. The first car covers 180 kilometers in the same time the second car covers 135 kilometers. What is the average speed of each car?
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Car II rate = x kph
D=135
Car I rate = x+20 kph
D=180
time is same
t=d/r
180/(x+20)=135/x
cross multiply
180x=135(x+20)
180x=135x+135*20
45x=135*20
/45
x=135*20/45
x=60 kph Car II
Car I = 60 +20 = 80 kph