Question 206786
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.