Question

The diameter of a circular park is 70 m if the cost of cementing this park is 1000₹ per 100 m ² than find the total cost of cementing this park take π=3.14​

Answer 1

Answer :-

• Total cost of cementing the park = 38465 Rs

Given :-

• Diameter of park = 70 m
• Rate of cementing = 1000 Rs / 100 m²
• Value of pi (π) = 3.14

To Find :-

• Total cost of cementing the park = ?

Explanation :-

As above given, we have to find the total cost of cementing the park and thus, first we need to find it's area.

Finding radius of park,

$\blue { \boxed { \bf \bigstar \: Radius \: of \: Park = \dfrac{Diameter}{2} \: \bigstar }}$

$\sf : \; \leadsto \dfrac{70}{2} \: m$

$\sf : \; \leadsto 35 \: m \qquad \star$

Finding area of park,

$\pink { \boxed { \bf \bigstar \: Area \: of \: Park = \pi r^2 \: \bigstar }}$

$\sf : \; \leadsto 3.14 \times (35)^2 \: m^2$

$\sf : \; \leadsto 3.14 \times 35 \times 35 \: m^2$

$\sf : \; \leadsto 3.14 \times 1225 \: m^2$

$\green { \bf : \; \leadsto 3846.5 \: m^2 \qquad \star }$

Finding the cost of cementing,

$: \: \leadsto \text{ \sf Cost of cementing 100 \sf m^2 } = \bold{1000 \: R_S}$

$: \: \leadsto \text{ \sf Cost of cementing 1 \sf m^2 } = \dfrac{1000}{100} \: R_S = \bold{ 10 \: R_S}$

$: \: \leadsto \text{ \sf Cost of cementing 3846.5 \sf m^2 },$

                     $\sf = (3846.5 \times 10) \; R_S$

                    $\red { \underline { \boxed { \bf = 38465 \; R_S }}}$

Hence, the total cost of cementing the park is 38465 Rs.