Question

the perimeter of a rectangle is 240 CM if its length is increased by 10% and its breadth is decreased by 20% we get the same perimeter find the length and breadth of the rectangle​

Answer 1

Answer:

length = 30cm

breadth = 40 cm

Answer 2

Answer:

L = 80 cm, B = 40 cm

Step-by-step explanation:

Let L and B be the length and breadth of the rectangle.

Perimeter is => 2(L+B) = 240 .

New length = 1.1 L

New Breadth = 0.8B

New perimeter is => 2(1.1L+ 0.8B) = 240

//since perimeter remained the same.

2(L+B) = 2(1.1L + 0.8B)

L + B = 1.1 L + 0.8B

1.1 L - L = B - 0.8B

0.1 L = 0.2B => L = 2B.

//Substitute in any equation

2(L+B) = 240

2(2B+B) = 240 => 6B = 240 => B = 40 cm.

L = 2B = 80 cm