Divide the rectangle 30 cm long and 12 cm wide into two parts, so that one part is 4 times larger

Divide the rectangle 30 cm long and 12 cm wide into two parts, so that one part is 4 times larger than the other. Find the area of each piece.

Let’s determine the area of the original rectangle, knowing that, by definition, it is equal to the product of its length and its width:

30 * 12 = 360.

We denote by the variable x the area of the smaller part of this rectangle.

Then, according to the condition of the problem, the area of the greater part will be equal to 4x cm2.

Knowing that the total area of the parts is 360 cm2, we draw up an equation and find the area of each part:

x + 4x = 360;

5x = 360;

x = 72;

360 – 72 = 288.

Answer: The areas of the parts of the rectangle are 72 cm2 and 288 cm2.