Two cars are traveling at speeds of 120 kilometers per hour and 90 kilometers per hour respectively. If the faster one travels for 4 hours longer than the slower one and also goes twice as far, how far did the slow one travel?
Let the distance covered by the slower car = D
Let the time taken by the slower car = T
90T = D......................(1)
120*[T+4] = 2D..........(2)
T = 8 hours - time taken by the slower car.
D = 720 km - distance travelled by the slower car.
x = slower car time x+4 = faster car time
120 (x+4) = 2 (90) x
120x + 480 = 180 x
x = 8 hours 8hours at 90 k/hr = 720 km