Question

A wire is in the shape of a square of perimeter $64cm$. A rectangle is formed with this wire such that its length is $20cm$. Then, the area of the rectangle is _____.

• A. $880{cm}^2$
• B. $240{cm}^2$
• C. $350{cm}^2$
• D. $256{cm}^2$

Answer 1

Answer: (B)

Let the breadth of the rectangle be $b.$

As the length of wire remain constant in this process perimeter of square will be equal to perimeter of rectangle,

$64=2(l+b)$

$\Rightarrow$ $64=2(20+b)$

$\Rightarrow$ $32=20+b$

$\Rightarrow$ $b=12cm$

So, area of the rectangle will be product of length and breadth,

$A=l\times b$

$\Rightarrow A=20\times 12$

$\Rightarrow A=240c{m}^2$