SOLUTION: an automobile was moving with a speed of 15 m/s on a distance of 30.0 km then the rest of the trip of 40.0 km long it made in 1.0 h what was the average speed
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Question 1082113: an automobile was moving with a speed of 15 m/s on a distance of 30.0 km then the rest of the trip of 40.0 km long it made in 1.0 h what was the average speed Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! an automobile was moving with a speed of 15 m/s on a distance of 30.0 km then the rest of the trip of 40.0 km long it made in 1.0 h what was the average speed
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Change 15 m/s to km/h: = 54 km/h
We know the total dist: 30 + 40 = 70 km
let s = average speed for the trip
write a time equation; time = dist/speed + 1 =
multiply equation by 54s, cancel the denominator
30s + 54s = 54(70)
84s = 3780
s = 3780/84
s = 45 km/h is the average speed
:
:
See if that checks out, find the actual times
30/54 = .55 hrs first 30 km
40km time 1 hr
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70/45 = 1.55 hrs time of the whole trip
