Divide a square sheet of paper with a side of 2dm into five equal rectangular pieces. Find the area of one piece

Method I.

Let’s find the area of ​​this square, for this we first translate dm into centimeters:

2dm = 20 cm (1dm = 10 cm).

The area of ​​a square is equal to the square of its side:

S = a² = 20² = 400 (cm²).

Therefore, the area of ​​each of the resulting rectangles (since they are equal in area) is equal to 400: 5 = 80 (cm²).

Method II.

Divide the square into 5 equal rectangles. The length of the resulting rectangle will be equal to the side of the square, and the width will be 5 times less (that is, we make cuts on one side to get 5 rectangles).

This means that you get 5 rectangles with sides 20 (cm) and 20: 5 = 4 (cm).

Let’s find the area of ​​the resulting rectangle: 20 * 4 = 80 (cm²).