Describe the steps you would use to solve this problem.

Question

In a scale drawing of a dining room floor plan, 10 mm equals 2 meters. If the homeowners wanted to purchase flooring that costs $10.89 per square yard, how much would they spend on flooring for the dining room? The dimensions of the dinning room on the foor plan are 44 mm X 32 mm.

Answer 1

This silly designer is switching between english units (yards) and metric (mm, and m) to confuse us. 

 

first let's convert our price per square yard to square meters for simplicity

 

($10.89/1 yard²) * (1 yard² / 0.836127 m²) = $10.89/0.836127 m² = $13.0243372119/m² 

 

now we have an ugly number of $ per 1 m² of flooring. Don't worry we can figure out how many significant figures to use at the end.

 

we also know that in the drawing 10 mm = 2 meters in real life

 

given that the dimensions are 44 mm X 32 mm let's convert these to actual meters

 

44 mm * (2 meters / 10 mm) = 8.8 meters

 

32 mm * (2 meters / 10 mm) = 6.4 meters 

 

and the total area of the floor in meters is 8.8 m X 6.4 m = 56.32 m²

 

Finally, we need to find how much our cost will be,

 

$13.0243372119/m^{2 *} (56.32 m²) = $733.530671776 

 

in this case it only makes sense to use numbers up to two decimal places, though if you're a real stickler for significant figures it should be less.