The length of the rectangle is 12 cm, the width is 1/4 of the length. find the perimeter of the rectangle.

From the conditions of the problem, we are given: the length of the rectangle, which is 12 cm. It is known that the width is 1/4 of its length. You want to know the perimeter of this rectangle. We calculate the length of the rectangle: 12 x 1/4 = 12/1 x 1/4 = 12/4 = 3 cm width of the rectangle. We find the perimeter: P = 2 x (a + b) = 2 x (3 + 12) = 2 x 15 = 30 cm.
Answer: P of the rectangle = 30 cm.