Andy has a square picture with sides that are each 5 inches long. Isabel has this rectangular picture.
What is the difference, in inches, between the perimeters of Andy’s picture and Isabel’s picture?
The perimeter of Andy's picture is 5+5+5+5 = 20 inches.
Isabel's picture is rectangular with two sides that are each 5 inches long and two sides that are each 3 inches long. The perimeter is 5+5+3+3 = 16 inches.
The difference between the perimeters is 20 - 16 = <<20-16=4>>4 inches. Answer: \boxed{4}.