The area of the rectangle is divided into two parts in a ratio of 2: 7.
The area of the rectangle is divided into two parts in a ratio of 2: 7. Calculate the area of each part if the sides of the rectangle are 1 dm and 9 cm.
1) Find the area of the rectangle. The area of a rectangle is equal to the product of its sides S = ab.
1 dm = 10 cm
S = 10 * 9 = 90 (cm ^ 2).
2) Find the area of each part.
Let the area of one part be x cm ^ 2, then the area of the first part is 2x cm ^ 2, and the area of the second part is 7x cm ^ 2. By the condition of the problem, it is known that the area of both parts of the rectangle is (2x + 7x) cm ^ 2 or 90 cm ^ 2. Let’s make an equation and solve it.
2x + 7x = 90;
9x = 90;
x = 90: 9;
x = 10 (cm ^ 2);
2x = 2 * 10 = 20 (cm ^ 2) – the area of the first part;
7x = 7 * 10 = 70 (cm ^ 2) – the area of the second part.
Answer. 20 cm ^ 2, 70 cm ^ 2.