posted by karen .
If a van travels for a distance of 18 km at an average speed of 75 km/h and then for a distance of 63 km at an average speed of 90 km/h, what is the total time for the journey in minutes, to the nearest minute?
time = distance/speed
18/75 + 63/90 = 0.24 + 0.70 = 0.94 hr = 56.4 min
or, 56 min