Answer:
The dimensions on the blueprints are 0.9 inches and 0.8 inches
Step-by-step explanation:
* Lets explain the relation between the drawing dimensions and
 the real dimensions
- A scale drawing make a real object with accurate sizes reduced
 or enlarged by a certain amount called the scale
- Ex: If the scale drawing is 1 : 10, so anything drawn with the size of
 1 have a size of 10 in the real so a measurement of 15 cm on the
 drawing will be 150 cm on the real
- In a scale drawing, all dimensions have been reduced by the same
 proportion
* Lets solve the problem
- On a set of blueprints for a new home, the contractor has
 established a scale of 0.5 in : 10 ft
∵ The drawing scale ratio must be in same unit
∴ Change the feet to inch
∵ 1 foot = 12 inches
∴ 10 feet = 10 × 12 = 120 inches
∴ The scale is 0.5 inches : 120 inches
- Simplify the scale by multiply it by 2
∴ The scale is 1 in : 240 in
- Lets find the dimensions on the blueprints
∵ The real dimensions are 18 feet and 16 feet
- Change the feet to inches
∴ 18 feet = 18 × 12 = 216 inches
∵ 16 feet = 16 × 12 = 192 inches
∵ The scale is 1 : 240
∴ 1/240 = x/216 ⇒ use cross multiplication
∴ 240 x = 216 divide both sides by 240
∴ x = 0.9 inch
∵ The scale is 1 : 240
∴ 1/240 = y/192 ⇒ use cross multiplication
∴ 240 y = 192 divide both sides by 240
∴ y = 0.8 inch
* The dimensions on the blueprints are 0.9 inches and 0.8 inches
