Question

The area of a circular field is 154sq.m. Find the time taken by an athlate to complete 2 rounds if she is jogging at the rate of 5km/hr

Answer 1

$\pi$r^2=15m^2
22/7r^2=154
r^2=49
r=7m
Circumference2$\pi$r=2*22/7*7=44m
2rounds=2circumference=2*44=88m=0.088km
speed=5km/hr
time=Total circumference/speed=0.088/5=0.0176hr