SOLUTION: I am having a problem answering this problem,Please help. Barn painting. Melanie can paint a certain barn by herself in x days. Her helper Melissa can paint the same barn by h

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: I am having a problem answering this problem,Please help. Barn painting. Melanie can paint a certain barn by herself in x days. Her helper Melissa can paint the same barn by h      Log On


   



Question 206786: I am having a problem answering this problem,Please help.
Barn painting. Melanie can paint a certain barn by herself
in x days. Her helper Melissa can paint the same barn by
herself in 2x days. Write a rational expression for the fraction
of the barn that they complete in one day by working
together. Evaluate the expression for x = 5.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Melanie can paint a certain barn by herself
in x days. Her helper Melissa can paint the same barn by
herself in 2x days. Write a rational expression for the fraction
of the barn that they complete in one day by working
together.
------------
Melanie does 1/x of the barn per day.
Helper does 1/2x per day.
Together, they do 1/x + 1/2x per day, = 3/2x --> 2x/3 days to do the job.
----------------------
Evaluate the expression for x = 5.
For x = 5:
3/(2*5) = 3/10 per day. ---> 10/3 days to do the job.