The length of the rectangle is 3.6 dm and the width is 75% of the length, we calculated the area

The length of the rectangle is 3.6 dm and the width is 75% of the length, we calculated the area and perimeter of the rectangle.

Let us determine, by making a proportion, the width of the rectangle, if it is 75% of its length, equal to 3.6 dm (we will take it as 100%):

x = 75%,

3.6 dm = 100%.

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

x = 3.6 * 75: 100 = 270: 100 = 2.7 dm.

Perimeter – the sum of all sides, calculated by the formula:

P = 2a + 2b = 2 * 3.6 + 2 * 2.7 = 7.2 + 5.4 = 12.6 dm.

S = a * b = 3.6 * 2.7 = 9.72 dm² – area.