how lond wil it take to paint the same mural on a 15-ft-by-27-ft wall?

Question

It takes 12h to paint a 10ft by 18ft mural. How long will it take the same number of people to paint the same mural on a 15ft by 27ft wall?

Answer 1

The area of the mural is 10×18=180 sq ft. So it takes 12 hours to paint 180 sq ft. 1 sq ft takes 12/180=1/15hr (4 minutes).

To paint a larger mural with area 15×27=405 sq ft takes 405/15=27 hours (15×27÷15).