Question

Fencing was provided to a circular field for which total cost was 220 if the cost per meter was 50 paise what was the radius of the field
80m,120m,70m, 100m

Answer 1

why not try a square field

Answer 2

$2\pi \: r \times 50 \div 100 = 220 \\ r = 220 \times 100 \times 7 \div 50 \times 2 \times 22 \\ r = 10 \times 7 = 70m$