Question

Ying Zyiyu covered the first 300 miles of a trip going at 60 mph and the last hundred going at 40 mph. What was his average speed for the entire trip?

NEED IN 5 MINUTES

Answer 1

Average speed is (total distance)/(total time).

To find the total time we need to do some division.

Time for 200 miles=200/50=4 hours.

Time for 100=100/40=5/2 hours.

Total time=13/2 hours. Total distance=200+100=300 miles.

Av speed=300/(13/2)=300×2/13=600/13=46.15 mph approx.