Calculate the average speed of the train

Question

A train moved at a speed of 90 miles per hour for 2 hours and then slowed down to 72 miles per hour for the next 30 minuteso

Answer 1

Total distance traveled        Time

90×2=180 miles                   2 hrs

72×1/2=36 miles                  1/2 hr

 

216miles  total                      2 1/2 hours

Average speed 216 mi/(2 1/2 hr)=86.4 mph