Find the perimeter draw a rectangle with sides 4 cm five millimeters and 5 cm find its perimeter.

The perimeter of a rectangle is equal to the sum of all its sides P = a + a + b + b. Imagine the sides of the rectangle a and b in millimeters. 1 cm = 10 mm, we have 4 cm 5 mm = 4 * 10 mm + 5 mm = 45 mm, and 5 cm = 5 * 10 mm = 50 mm. P = 45 mm + 45 mm + 50 mm + 50 mm = 90 mm + 100 mm = 190 mm = 19 cm.Answer: the perimeter of the rectangle is 19 cm.