Question

The length of a rectangle is three times the breadth. If the minimum perimeter of the rectangle is $160 cm$, then

• A. breadth $>20 cm$
• B. length $<20 cm$
• C. breadth $\geq 20 cm$
• D. length $\leq 20 cm$

Answer 1

Answer: (C)

Let breadth of rectangle be $x cm$.
$\therefore \text { Length of rectangle } =3 x$
$\text { Perimeter of rectangle } =2(\text { Length }+\text { Breadth })$
$ =2(x+3 x)=8 x$
$\text { Given, } \text { Perimeter } \geq 160 cm $
$8 x \geq 160$
Dividing both sides by 8 ,
$x \geq 20 cm$