The area of a circular field is 3850m2. Find the cost of fencing the field at Rs.4 per meter.

A Rs. 889.85

B Rs. 808

C Rs. 880

D Rs. 885.6

E None of these

Correct Answer: Option C

Area = 3850m2

We know that area of a circle = πr², where r is the radius of the circle

Therefore, 3850 = πr²

22/7 r² = 3850 (taking π = 22/7)

r² = (3850 × 7)/22

r² = 1225

r = 35 m

We know that the cost of fencing = perimeter of the field × cost per meter

Perimeter of the field = 2 π r = 2 × 22/7 × 35 [perimeter of circle = 2 π r]

= 220 m

Therefore the cost of fencing = Rs. (220 × 4)

= Rs. 880

Hence, the cost of fencing the field is Rs. 880.