A train travels 60 miles per hour for 3 hours and then 45 miles per hour for 2 hours. What is the train’s average speed in miles per hour during the 5‑hour period?

Explanation:

Average speed is given by

Total distance/ total time taken

So we need to know the distance in the first travel

Then

First part

Speed=60miles/hour

Time 3hours

Distance = speed × time

Distance = 60×3

Distance = 180 miles

Second part

Speed 45mile/hour

And time is 2hours

Distance = speed × time

Distance = 45× 2

Distance = 90miles

So total distance travelled for both cases is 90+180=270miles

And total time is 5hours

Then,

Average speed = total distance/total time

A.S=270/5

A.S= 54miles/hour

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