Answer:
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