Question

The length of a rectangle is inversely proportional to it's breadth. When the length is 5m the breadth is 2m, what will be the length of the breadth is 2.5m ?​

Answer 1

Answer:

4 m

Step-by-step explanation:

Length of the rectangle is inversely proportion to the breadth.

length ∝ 1/breadth

 l ∝ 1/b

Let l = k/b      , where k is any constant.

when length = 5, breadth = 2.

⇒ 5 = k/2

⇒ 5 * 2 = k

⇒ 10 = k

   Hence, when breadth = 2.5

⇒ l = k/b  

⇒ l = 10/2.5

⇒ l = 4

     Length of the rectangle is 4 m

Alternatively,length ∝ 1/breadth means,

length x breadth is constant, l₁b₁ = l₂b₂ = l₃b₃ = lₙbₙ

 ⇒ 5 x 2 = length x 2.5

 ⇒ 10/2.5 = 4 = length

Answer 2

Given :-

Length = 5 m

Breadth = 2m

Breadth (new) = 2.5 m

To Find :-

New length

Solution :-

length ∝ 1/breadth

Let

1 = k

Length = l

Breadth = b

Now

l = k/b

5 = k/2

10 = k

Now

l = 10/2.5

l = 4 m

${\textsf{\textbf{\pink{\underline{Length = 4 m}}}}}}$