SOLUTION: A bus enters a highway driving 55 mph. A car enters the highway at the same place 5 mins later and drives 70 mph in the same direction. From the time the car enters the highway, ho

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Question 709159: A bus enters a highway driving 55 mph. A car enters the highway at the same place 5 mins later and drives 70 mph in the same direction. From the time the car enters the highway, how long will it take the car to pass the bus?(round to the nearest tenth of a minute)
Answer by josgarithmetic(39620) About Me  (Show Source):
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Start time begins at 0 when the car enters the freeway. The bus has reached a certain distance along or on the freeway when the car begins on the freeway at time 0.

What distance did the bus travel before the car reached the freeway? 55%2A%281%2F12%29 miles. Five minutes is one twelfth of an hour.

How much distance on the freeway will bus and car travel when they match in this distance?
BUS: 55%2A%281%2F12%29%2B55%2At
CAR: 70%2At

We do not know the value of that distance but the variable there is TIME, which is what we are asked to find.

So both those distances must be equal when the car reaches the bus.
highlight%2855%2F12%2B55t=70t%29, solve for t, hours. Note, 60 minutes is 1 hour.

Continuing...,
55%2F12=70t-55t
55%2F12=15t
11%2F12=3t, because we can divide both sides by 5
11%2F%2812%2A3%29=t
highlight%28t=11%2F36%29 that is hours.
highlight%28%2811%2F36%29%2A60=18%261%2F3%29 minutes. Or, 18 minutes and 20 seconds.