Question

Each side of a triangle is increased by 10 cm. If the ratio of perimeter of the new Triangle and the given triangle is 5:4. find the perimeter of the given Triangle.

Answer 1

Answer:

120 cm

Step-by-step explanation:

Let the original perimeter be x .

Increasing each side by 10 means to increase the perimeter by 30 .

New perimeter = x + 30 .

Ratio = 5 : 4 .

( x + 3 0 ) / x = 5 / 4

⇒ 4 x + 120 = 5 x

⇒ x = 120

Hence the perimeter is 120 cm .

Answer 2

Solution:

Suppose the original perimeter be k .

Now,
Increasing each side by 10 means we increase the perimeter by 30 .

Therefore, New perimeter = k + 30 .

Given, Ratio = 5 : 4 .

( k + 30 ) / k = 5 / 4

⇒ 4 k + 120 = 5 k

⇒ 120 = 5 k - 4 k

⇒ k = 120


Therefore, the required perimeter is 120 cm .