Problema Solution

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 provided by our tutors

Melanie can paint a certain barn by herself in x days

So In 1 day, Melanie can paint 1/x portion of barn

Her helper Melissa can paint the same barn by herself in 2x days.

So In 1 day, Melissa can paint 1/2x portion of barn

So, in one day, combine they can paint = 1/x + 1/2x

Taking LCM = 2x , we get = 2/2x +1/2x = 3/(2x)

For x=5, it is 3/2*5 = 3/10