SOLUTION: Hi A car left town A for town B. Another car left town B for town A at the same time. The ratio of the speeds of the 2 cars were 6:5 respectively. After the stwo cars passed each

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Question 1201475: Hi
A car left town A for town B. Another car left town B for town A at the same time. The ratio of the speeds of the 2 cars were 6:5 respectively. After the stwo cars passed each other car A speed was reduced by 1/6 and car B was reduced by 1/4 . When car A arrived at town B car B was still 54km from town A. What is the distance between A and B.
Thanks

Answer by ikleyn(52754) About Me  (Show Source):
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A car C1 left town A for town B. Another car C2 left town B for town A at the same time.
The ratio of the speeds of the 2 cars were 6:5 respectively.
After the stwo cars passed each other car A speed was reduced by 1/6 and car B was reduced by 1/4 .
When car A arrived at town B car B was still 54km from town A. What is the distance between A and B.
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Let d be this unknown distance between A and B, in kilometers.

The speed of the car C1 was initially 6x; the speed of the car C2 was initially 5x.
where x is some common measure of the speeds, in km/h.


The time from the start to the passing moment was  d%2F%286x%2B5x%29 = d%2F%2811x%29  hours.


The distance traveled by car C1 from A to the passing point was  time*speed = %28d%2F%2811x%29%29%2A6x = %286%2F11%29%2Ad  hours.
The remaining distance for car C1 was  %285%2F11%29d  kilometers.


The distance traveled by car C2 from B to the passing point was  time*speed = %28d%2F%2811x%29%29%2A5x = %285%2F11%29%2Ad  kilometers.


The speed of the car C1 after the passing moment was %286x-%281%2F6%29%2A6x%29 = 6x-x = 5x  km/h.

The speed of the car C2 after the passing moment was %285x-%281%2F4%29%2A5x%29 = %283%2F4%29%2A5x = 3.75x  km/h.


To travel from the passing point to B, car's C1 travel time was  %28%285%2F11%29%2Ad%29%2F%285x%29 = d%2F%2811x%29 hours.
During this time, car C1 traveled the distance  %285x%29%2A%28d%2F%2811x%29%29 = %285%2F11%29%2Ad km.            (1)


During the same time, car C2 traveled the distance %283.75x%29%2A%28d%2F%2811x%29%29 = %283.75%2F11%29%2Ad km.    (2)


The sum of distances (1), (2) and 54 km is exactly d

    %285%2F11%29d%29%29 + %283.75%2F11%29d%29%29 + 54 = d.     (3)


Multiply by 11 both sides of equation (3)

    5d + 3.75d + 594 = 11d.


Simplify and find d

    8.75d + 594 = 11d

    594 = 11d - 8.75d

    594 = 2.25d

     d  = 594/2.25 = 264.

ANSWER.  The distance from A to B is 264 kilometers.

Solved.