A painter has painted a picture on a piece of canvas that measures 10 × 14 inches. In order to accommodate a frame, he has left an un-painted margin of 1 inch all the way around. What part of the canvas has been painted?
The area of the entire piece of canvas = 10 inches × 14 inches = 140 square inches.
The portion painted on equals 8 inches × 12 inches = 96 square inches. (This is determined by subtracting 1 inch from the length of each side to account for the margin.)
The portion used for painting can be expressed as a fraction: 96/140.
Reduce this fraction (divide 96 by 140) to determine that 68,5% of the canvas is covered with paint.