SOLUTION: You drive on Interstate 10 from Lafayette to Houston, half the time at 56 km/h and the other half at 70 km/h. On the way back you travel half the distance at 56 km/h and the other

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: You drive on Interstate 10 from Lafayette to Houston, half the time at 56 km/h and the other half at 70 km/h. On the way back you travel half the distance at 56 km/h and the other       Log On

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Question 560495: You drive on Interstate 10 from Lafayette to Houston, half the time at 56 km/h and the other half at 70 km/h. On the way back you travel half the distance at 56 km/h and the other half at 70 km/h.
(a) What is your average speed from Lafayette to Houston?
km/h
(b) What is your average speed from Houston back to Lafayette?
km/h
(c) What is your average speed for the entire trip?
km/h
(d) What is your average velocity for the entire trip?
km/h

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


a. Let represent time for the entire trip. Then represents the amount of time at 56 km/h. And also represents the amount of time at 70 km/h. Distance equals rate times time, so the distance traveled at 56 km/h is . The distance traveled at 70 km/h is . The sum of these distances is the total distance, , from Lafayette to Houston, so





Since distance equals rate times time, rate equals distance divided by time. Hence the average speed from L to H is 63 km/h.

Write back and I'll give you a quote to do the rest of this.

John

My calculator said it, I believe it, that settles it
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