Question

A man walks around a circular park 4 times in 12 minute . The radii of the park is 49m . Find the speed if man in km/h (use
$\pi = 22by7$

$\pi$

Answer 1

circumference of circular park = pie×2×r

=22/7×2×49

=44×7

=308 m

Total distance travelled = 308×4

=1232m

=1232/1000 km

Total time taken= 12 min

=12/60 hours

=1/5

speed = 1232/1000×5

=1232/200

=6.16 km/h

Answer 2

Distance covered =
$4 \times 2\pi \: r \\ = 8 \times \frac{22}{7} \times 49 \\ = 8 \times 154 = 1232$
Time is 12 minutes = 12/60 hrs

Speed = distance/time
Speed = 1232/12/60
= 1232*60/12 m/hr
=1232*5 metre/hr
=6160/1000 km /hr
=6.16 km /hr