Question

Perimeter of a rectangle is equal to the perimeter of square whose area is 400 cm^2.Find the area of rectangle if length of rectangle is 40% more than the side of square​

Answer 1

Step-by-step explanation:

Perimeter of the square = 400cm²

Also, Perimeter of the square = a*a

Therefore, a*a = 400

=a² = 400

=a = $\sqrt{400}$

=a = 20cm (Side of the square)

According to question, length of the rectangle is 40% more than side of the square.

Therefore, 20 + 40% of 20

= 20 + 40*20/100

= 20 + 6

= 26cm (Length of rectangle)

To find the breadth of the rectangle:-

We know, perimeter of a rectangle is equal to the perimeter of square.

Therefore, perimeter of square = Perimeter of rectangle = 4a = 4*20 = 80cm

We know, 2(l + b) is the formula for perimeter of rectangle.

Therefore, 2(l + b) = 80

=l + b = 40

=26 + b = 40

=b = 40 - 26 = 14cm

Therefore,  area of the rectangle = l*b = 14*26 = 364cm² (Ans).

Here is your answer. Hope it helps!

Answer 2

Answer:

Perimeter of the square = 400cm²

Also, Perimeter of the square = a*a

Therefore, a*a = 400

=a² = 400

=a =  

=a = 20cm (Side of the square)

According to question, length of the rectangle is 40% more than side of the square.

Therefore, 20 + 40% of 20

= 20 + 40*20/100

= 20 + 8

= 28cm (Length of rectangle)

To find the breadth of the rectangle:-

We know, perimeter of a rectangle is equal to the perimeter of square.

Therefore, perimeter of square = Perimeter of rectangle = 4a = 4*20 = 80cm

We know, 2(l + b) is the formula for perimeter of rectangle.

Therefore, 2(l + b) = 80

=l + b = 40

=28 + b = 40

=b = 40 - 28 = 12cm

Therefore,  area of the rectangle = l*b = 12*26 = 336cm²