SOLUTION: two cars leave an intersection at the same time and travel in opposite directions. one car travels at 20mph and the other car travels at 60mph how long will it take for the two car

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Question 62947: two cars leave an intersection at the same time and travel in opposite directions. one car travels at 20mph and the other car travels at 60mph how long will it take for the two cars to be 240 miles apart?
Found 2 solutions by funmath, 303795:
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
two cars leave an intersection at the same time and travel in opposite directions. one car travels at 20mph and the other car travels at 60mph how long will it take for the two cars to be 240 miles apart?
The formula for distance: highlight%28d=rt%29, d=distance, r=rate or speed, t=time.
For the first car:
r=20 m/h
t=x
d=20x
For the other car:
r=60 m/h
t=x
d=60x
If you add the two distances together you get 240.
20x+60x=240
80x=240
80x/80=240/80
x=3
It takes x=3 h.
Happy Calculating!!!

Answer by 303795(602) About Me  (Show Source):
You can put this solution on YOUR website!
Using the idea that one car travels 20 miles in one hour and the second travels 60 miles in an hour then the cars are getting further apart at a rate of 80 miles per hour (their combined speed is 80 miles per hour).
The time taken to travel 240 miles at a speed of 80 miles per hour is 240/80 = 3 hours