Question 1070899
should be.
if r = 90, then r - 20 = 70
the rate of the faster car is 90 kmph.
the rate of the slower car is 70 kmph.


90 kmph * 3 hours = 270 km.
70 kmph * 3 hours = 210 km.


if they meet in the middle somewhere, then the total km traveled has to be equal to 480.


i think that's all you need to do to check your figures.