Question 180629
Melanie can paint a certain barn by herself in x days. Her helper melissa can
 paint the same barn by herself in 2 xdays. 
write a rational expression for the fraction of the barn that they complete in
 one day by working together.
:


{{{1/x}}} + {{{1/(2x)}}} 
{{{(2 + 1)/(2x)}}} = {{{3/(2x)}}}
:
 evaluate the expression for x=5
{{{3/(2(5))}}} = {{{3/10}}} is the fraction of the barn painted in 1 day working together