The length and breadth of a rectangle are in the ratio 7:5 andits area is 3500 sq.cm. What is the perimeter of the rectangle. in cm?

As per given in the question,

Let,the length be $$7x$$ and breadth be $$5x$$

We know that the area of the rectangle $$=length\times breadth$$

So, $$3500=7x\times 5x$$

$$\Rightarrow 3500=35\times x^2$$

$$x=10$$cm

We know that the perimeter of the rectangle $$ =2(length+breadth)$$

hence, perimeter $$=2(7x+5x)$$

$$\Rightarrow 2\times 12x$$

$$\Rightarrow 24\times 10=240$$

therefore,the perimeter of the rectangle is 240 cm