Answer:
Explanation:
Ryan will take 5 weeks and 5 days to complete the tree house.
What is unitary method?
'The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.'
According to the given problem,
Time taken by Ryan to complete building the tree house = 85 hours
= hours
Hours he work on the tree house = 15 hours
=
Weeks taken by Ryan to complete building = ÷ = 5.5 weeks
= 5 weeks 5 days
Hence, we can conclude that Ryan is going to take 5 weeks and 5 days to complete building the tree house.