SOLUTION: A truck traveled the first 200 miles of a trip at one speed and the last 225 miles at the average speed of 5 mph less. the entire trip took 10 hours. what were the two average spee

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Question 750254: A truck traveled the first 200 miles of a trip at one speed and the last 225 miles at the average speed of 5 mph less. the entire trip took 10 hours. what were the two average speeds?
So far I have tried 200x+250(x-5)=10 and I got x=2.8 and -2.2 which is obviously wrong. Please help!
Answer by josgarithmetic(39838) About Me  (Show Source):
You can put this solution on YOUR website!
Basic concept is rate*time=distance. rate is miles per hour, time is hours, distance is miles.

You know the total time but you do not know each individual time for the two distances. Know to do this:

r%2At=d
r%2At%2Fr=d%2Fr
t=d%2Fr---------which you can use.

First Part, rate is r.
Second part, rate is r-5.

highlight%28200%2Fr%2B225%2F%28r-5%29=10%29
The sum of the two parts of the times for the trip is 10 hours. See, the equation has some rational parts, meaning take the form of fractions.