Question 311386
Melanie can paint a barn in x days
So she does 1/x of job in 1 day.
..
Melissa does it in 2x days.
so she does 1/2x of the job in 1 day.
..
Together they do 1/x + 1/2x of the job in 1 day

=3/2x of the job in 1 day.

if x =5

3/10 of the barn they will paint together in 1 day