SOLUTION: two cars are traveling and leave in opposite directions at the same time. One car is traveling 20 mph faster than the other car. After 6 hours they are 780 miles apart. what is the

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Question 1026096: two cars are traveling and leave in opposite directions at the same time. One car is traveling 20 mph faster than the other car. After 6 hours they are 780 miles apart. what is the speed of the two cars?
I have tried to divide 780 by 6 then subtract 20 to find the speed, but im not sure that's how you are supposed to solve this question.

Found 3 solutions by josgarithmetic, mananth, MathTherapy:
Answer by josgarithmetic(39632) About Me  (Show Source):
You can put this solution on YOUR website!
RT=D basic travel rates rule
fast car       r+20        6         %28r%2B20%29%2A6
slow car       r           6          r%2A6
total                                 780

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
car I x mph
car ii x+ 20 km/h
..
They are moving towards each other

So add up their speed.

combined speed = x+ 1 x 20
( 2 x + 20 )
Time = 6 hours
Distance = 780 miles
Distance = speed * time
( 2 x 20 )* 6 = 780
12.00 x + 120 = 780
12 x = 780 + -120
12 x = 660
/ 12
x= 55 mph
car I = 55 mph
car ii 55 + 20 = 75 km/h
m.ananth@hotmail.ca

Answer by MathTherapy(10559) About Me  (Show Source):
You can put this solution on YOUR website!

two cars are traveling and leave in opposite directions at the same time. One car is traveling 20 mph faster than the other car. After 6 hours they are 780 miles apart. what is the speed of the two cars?
I have tried to divide 780 by 6 then subtract 20 to find the speed, but im not sure that's how you are supposed to solve this question.
Partially right!! I'm assuming they started from the same point, as opposed to a certain distance apart
When you divided 780 by 6, you got the combined speeds of the 2 cars
Let the slower car's speed be S
Then faster car's speed = S + 20
We then get: S + S + 20 = 130
2S = 110
S, or speed of slower car = 110%2F2, or highlight_green%28matrix%281%2C2%2C+55%2C+mph%29%29
Speed of faster car = 55 + 20, or highlight_green%28matrix%281%2C2%2C+75%2C+mph%29%29