Jane painted a 12ft. x 12ft. mural in 45 minutes. How long will it take to paint a 15ft. x 16ft. mural?
In order to paint 144 sq feet it will take 45 minutes
In order to paint 1 sq foot it will take 45/144 minutes
In order to paint 240 sq feet it will take:
45/144 x 240 minutes
= 75 minutes