Question

Периметр прямокутника - 40 см. Його ширина в 3 рази менша від довжини. Чому дорівнює площа прямокутника.

Answer 1

40 : 2 = 20 ( см ) сумма длины и ширины 
20 : ( 3 + 1 ) = 5 ( см ) ширина 
5 * 3 = 15 ( см ) длина 
15 * 5 = 75 ( cм² ) площадь 
ОТВЕТ 75 см²

Answer 2

Perimeter of a Rectangle

To find the perimeter of a rectangle, we need to know the length and width of the rectangle. In this case, we are given that the perimeter of the rectangle is 40 cm and that the width is 3 times smaller than the length.

Let's assume that the length of the rectangle is represented by the variable L and the width is represented by the variable W.

We can set up the following equations based on the given information:

1. The perimeter of a rectangle is given by the formula: Perimeter = 2 * (Length + Width). 2. The width is 3 times smaller than the length: Width = (1/3) * Length.

Using these equations, we can solve for the length and width of the rectangle.

Solving for the Length and Width

Let's substitute the second equation into the first equation to find the perimeter:

40 = 2 * (Length + (1/3) * Length)

Simplifying the equation:

40 = 2 * (4/3) * Length

40 = (8/3) * Length

To isolate the length, we can multiply both sides of the equation by (3/8):

Length = (40 * 3) / 8

Length = 15 cm

Now that we have the length, we can substitute it back into the second equation to find the width:

Width = (1/3) * 15

Width = 5 cm

Calculating the Area

The area of a rectangle is given by the formula: Area = Length * Width.

Substituting the values we found:

Area = 15 cm * 5 cm

Area = 75 cm²

Therefore, the area of the rectangle is 75 cm².

Please note that the calculations and formulas used in this response are based on the information provided in the question.