Question

The cost of fencing a circular field at the rate of rs 24 per metre is rs 5280. The field is to be ploughed at the rate of rs 0.50 per m2. Find the cost of ploughing the field

Answer 1

Answer:

Step-by-step explanation:

We first need to find the circumference of the circular field.....so we have...

 

5280/24  = 220m

 

Now....find the radius in meters

 

220  = 2*pi * r       divide by 2*pi

 

220/ (2 *pi)  = r

 

[110/pi ]   = r

 

So....the  area * cost per m^2  = total cost.....so we have

 

pi (110/pi)^2 * .5   ≈  rs 1926    [rounded]  

Answer 2

$\huge\tt{\blue{\underline{\mathfrak{Explanation:}}}}$

Given that:-

• The cost of fencing a circular field at the rate of rs 24 per metre is rs 5280.

• The field is to be ploughed at the rate of rs 0.50 per m^2.

To find:-

• The cost of ploughing the field.

______________________________

Length of the fence (in metres) = Total cost/Rate = 5280/24 = 220

As we know, the circumference of the field = 220 m

If r metres is the radius of the field, then 2πr = 220

2 × (22/7) × r = 220

r = (220 × 7)/ (2 × 22)

r = 35

Hence, the radius of the field = 35 m

Area of the field = πr^2

= (22/7) × 35 × 35

= 22 × 5 × 35 m^2

Cost of ploughing 1 m^2 of the field = Rs. 0.50

So, total cost of ploughing the field = 22 × 5 × 35 × Rs. 0.50 = Rs. 1925