Question

find the radius of the circle whose area is 161 square cm

Answer 1

Area = π × r ×r = 161


R × R = 161 × 7 / 22

R = 7.15cm approx

Answer 2

Area of circle = 161 cm^2
Area of circle = pie r^2
161 = 22/7*r^2
r^2 = 161*7/22
r = root1127/22

Hope this helps you.....:)