Actual Area of Room

On a floor plan drawn at a scale of 1:100, the area of a rectangular room is 30 cm^2. What is the actual area of the room?

A. 30,000 cm^2

B. 3,000 cm^2

C. 3,000 m^2

D. 30 m^2

After playing with precalculus for so long, this word problem should be a walk in the park but it is not. I will have to guess my way through.

I think 1:100 is a ratio and if so, then a fraction.

Let A = actual area of room

30 = (1/100)A

30/(1/100) = A

30(100) = A

3,000 cm^2 = A

I say the answer is B.