The perimeter of a rectangle is between 40 cm and 50 cm. If the ratio of its length to width is 5:7, what is the perimeter and area of the rectangle?

The perimeter of a rectangle is between 40 cm and 50 cm. If the ratio of its length to width is 5:7, what is the perimeter and area of the rectangle?

The sum of length and width is a multiple of 5 + 7 = 12
Then the perimeter is a multiple of 12 × 2 = 24
So the perimeter is 24 × 2 = 48 cm
The sum of length and width is 48 △ 2 = 24 cm
Length 24 × 7 ÷ (7 + 5) = 14 cm
Width 24-14 = 10 cm
So the area is 14 × 10 = 140 square centimeters

The circumference of a rectangle is 8 cm, and the length is twice the width. If the width is x cm, then the equation ()

If the width is x cm, the length is 2x cm
From the formula of the circumference of a rectangle
2（x+2x）=8
The circumference of a rectangle is 8 cm, and the length is twice the width. If the width is x cm, then the equation 2 (x + 2x) = 8 can be given

If the perimeter of the rectangle is 106CM, and the length is 1cm more than 3 times of the width, the area of the rectangle is 106CM______ cm2．

Let the length of the rectangle be YCM and the width be xcm. According to the meaning of the question, we can get y = 3x + 12 (x + y) = 106, the solution is x = 13y = 40, and the area of the rectangle is 40 × 13 = 520