The rectangle is 24.6 cm long, which is 120% of its width. Find the perimeter of the rectangle.

First of all, having made the proportion, we determine the width of the rectangle, provided that the length of 24.6 cm takes 120% of this value.

120% = 24.6.

100% = x.

Let’s write the equation, acting according to the “cross” rule and find the value of the variable:

x = 100 * 24.6: 120 = 2460: 120 = 20.5 cm.

The perimeter is the sum of all sides, for such a figure it corresponds to:

P = 2a + 2b = 2 * 24.6 + 2 * 20.5 = 49.2 + 41 = 90.2 cm.