SOLUTION: Two buses leave towns 732 km apart at the same time and travel toward each other. One bus travels 12 km/h slower than the other. If they meet in 3 hours, what is the rate of each

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Two buses leave towns 732 km apart at the same time and travel toward each other. One bus travels 12 km/h slower than the other. If they meet in 3 hours, what is the rate of each       Log On

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Question 1144627: Two buses leave towns 732 km apart at the same time and travel toward each other. One bus travels 12 km/h slower than the other. If they meet in 3 hours, what is the rate of each bus?
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
One bus travels 12 km/h slower than the other...
Let the faster bus's speed be r km/h.
Then the slower bus's speed is r-12 km/h.

...travel toward each other.
Since they travel toward each other, their speed of approach is the sum
of their speeds, r + r-12 which is 2r-12 km/h

...they meet in 3 hours,...
That means the distance between them goes from 732 km to 0 km in 3 hours.

...what is the rate of each bus?
Distance = (rate)(time)

732 = (2r-12)(3)

Divide both sides by 3

244 = 2r-12

Add 12 to both sides

256 = 2r

Divide both sides by 2

128 = r

So the faster bus went 128 km/h

The slower bus went 128-12 or 116 km/h

That's really fast!  So let's check how far each
went in 3 hours.

The faster bus went 128 km/h for 3 hours and therefore went (128)(3)=384 km.

The slower bus went 116 km/h for 3 hours and therefore went (116)(3)=348 km.

So their distances traveled until they met should add up to 732 km.  

And they do!:

384 km + 348 km = 732 km.

So the answers 128 and 116 km/h are correct. Hope they didn't get a ticket! lol
  
Edwin