The area of a circular playground is \[22176\] \[{{m}^{2}}\]. Find the cost of fencing this ground at the rate of Rs \[50\] per metre.

Home » The area of a circular playground is . Find the cost of fencing this ground at the rate of Rs per metre.

The area of a circular playground is

$22176$

${{m}^{2}}$

. Find the cost of fencing this ground at the rate of Rs

$50$

per metre.

The area of a circular playground is

$22176$

${{m}^{2}}$

. Find the cost of fencing this ground at the rate of Rs

$50$

per metre.

From the given question,

We got Area of the circular playground =

$22176$

${{m}^{2}}$

Let us consider r as the radius of the circle.

Therefore,

$\pi {{r}^{2}}=22176$

⇒

$(22/7){{r}^{2}}=22176$

⇒

${{r}^{2}}=22176\times (22/7)$

⇒

${{r}^{2}}=7056$

⇒

$r=84$

∴ we got Radius of the circular playground as

$84$

m

Now, we know that circumference of the circle =

$2\pi r$

=

$2\times (22/7)\times 84$

=

$528$

m

Cost of fencing one meter of ground = Rs

$50$

∴ Cost of fencing the total ground for Rs

$50$

Per mete = Rs

$528\times 50$

= Rs

$26,400$

i

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