Final answer:
To find the actual length of the wall, set up a proportion using the scale 1 inch to 12 feet. The actual wall would be 9 feet long since .75 inches on the plan scales up to 9 feet in reality based on the given ratio.
Step-by-step explanation:
The question involves a contractor looking at plans for a building a storage shed and asks how long the actual wall should be if the side of the building on the plans is .75 inches long with a scale of 1 inch to 12 feet. To solve this, we need to set up a proportion based on the scale given. We know that 1 inch on the plan corresponds to 12 feet in reality. Therefore, if the plan shows .75 inches, we can use the ratio 1 inch : 12 feet to find the actual length.
First, let's write the unit scale as a ratio 1 inch/12 feet. Then we can set up our proportion:
.75 inches / x feet = 1 inch / 12 feet
Now we can cross multiply to solve for x, the actual length of the wall in feet.
x feet = .75 inches * 12 feet / 1 inch
x feet = 9 feet
Hence, the actual wall should be 9 feet long.