Hi, it's my first time posting here and I need urgent help. I am doing a problem solving question for my Intermediate Algebra class and I am stuck on one particular question.

The question reads:

A Homeowner estimates that it will take her 8 days to roof her house. A professional roofer estimates that he could roof the house in 5 days. How long will it take if the homeowner helps the roofer?

Can someone please help? Thanks in advance.