Question

lenth of rectanle is 3.5 times of its breadth. if perimeter of rectangle is 180 cm. find the area of rectangle

Answer 1

Let the breadth of the rectangle be "x"

Given length of the rectangle is 3.5 times of Breadth , so length will be 3.5x

Perimeter of the rectangle = 180cm

$Perimeter = 2(l + b)$

$180=2(x+3.5x) \\ \\ </p><p>180=2x+7x \\ \\ </p><p>180=9x \\ \\ </p><p> \frac{180}{2} =X \\ \\ </p><p>90=x$

[substitute the values of x]

Length = 70cm , breadth = 20cm

To find area if the rectangle ➡

Length = 70cm , Breadth = 20cm

$Area \: of \: the \: rectangle \: = \: l \times b$

$= 70 \times 20 \\ \\ = 1400 {cm}^{2}$

Therefore area of the rectangle = 1400cm^2

Answer 2

Given,

perimeter of rectangle=180cm

to find,

area of rectangle =?

Now,

let the breadth of the rectangle = x

so,

length of rectangle = 3.5x

A/q

perimeter of rectangle = 2(l +b)

=> 180 = 2(3.5x+ x)

=> 180 = 2(4.5x)

=> 180 = 9x

=> x = 180/9

=> x = 20

breadth of the rectangle = 20cm

length of the rectangle = 3.5 × 20

= 70cm

Now,

calculate the area of rectangle:-

area of rectangle = l × b

= 70 × 20

= 1400cm²

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