The answer is D. 63. You have to set up a proportion as shwon in the image.
Answer:
32 hours.
Step-by-step explanation:
Let x represent the time taken by Russell and Aaron to build the shed.
We have been given that Russell and Aaron can build a shed in 8 hours when working together. Aaron works three times as fast as Russel.
Russell's work rate would be
.
Since Aaron works three times as fast as Russel, so Aaron's work rate would be
.
Part of work done by in one hour would be
.
We can represent our given information in an equation as:

Let us solve for x.




Therefore, it will take Russell 32 hours to build the shed working alone.