two snowplows are clearing a runway 2.56 miles long. crew a starts at one end and crew b starts at the other end. crew a is traveling .4 mph faster then crew b.

Question

after .5 hours they meet, how fast is each traveling

Answer 1

Chris,

    Here is how I solved this problem.

First of all , our basic formula for distance is d = rt, where d= distance, r= rate, and t = time.

The rate of snow plow a  = r.  The problem tell us that crew b travels .4 mph faster than a, so the rate for crew b

 = r + .4 . 

We know that t = .5 hours.

The distance that crew a travels is d = r x .5, or d = .5r

The distance that crew b travels is d = (r + .4) x .5.  Simplifying this gives us d= .5r + .2

Since they start at opposite ends and meet in the middle, the total distance they travel must be 2.56 miles.

So,  .5r + .5r + .2 = 2.56.

Combining like terms, we get r + .2 = 2.56, so r = 2.36.

So , crew a is traveling at 2.36 mph.

The rate for crew b is r + .4, which is 2.36 + .4 = 2.76 mph.

Hope this helps