Question

A person walks at the rate of 4km/h. How long will he take to go round square park 5 times, whose area is 2500 metre square

Answer 1

s=50
p=4×50
=200
distance=5×p=5×200=1000
s=v t
v=4km/h=10/9m/s
t=1000×9/10
=900sec

Answer 2

area=2500m^2
side of square=50m
$\sqrt{2500 {m}^{2} } = 50m$
perimeter of square=4×side=4×50m=200m
5 times of square=200m×5=1000m(1km)
time taken by the person to walk=15min
$\frac{4km}{60min} \times 1km = 1km \: per \: 15min$