A blueprint of a kitchen has a scale of 1/8 inch is equivalent to 1 foot. If the pantry measures 1/2 inch by 3/4 inch on the blueprint, what are the actual dimensions of the pantry?

Question

How many feet by how many feet?

Answer 1

1/8 inch : 1/2 inch = 1 ft : x ft
(1/8) / (1/2) = 1/x
(1/8)x = 1/2
multiply both sides by 8
x = 4
so the 1/2 inch on the blueprint represents 4 ft of actual dimension

or, even simpler:
1/8 inch : 1/2 inch = 1 ft : x ft
1 : 4 = 1 : x
x = 4, knowing the rules of ratios

repeat those steps for the 3/4 inch on the blueprint.