How many seconds will a boy take to run one complete round around a square field ofside 38 metres, if he runs at a speed of 6 km/h?

Correct option is A

Given:

Side of square field = 38 m

Speed of boy = 6 km/h

Formulas Used:

Perimeter of square field  = 4 $$\times \text{side}$$​​

Speed = $$\frac{\text{distance}}{\text{time}}$$​​

Solution:

Perimeter = $$4 \times 38 = 152 \text{ m}$$

Speed in m/s = $$6\times \frac{5}{18} = \frac{5}3 m/s$$​​

Time = $$\frac{152}{\frac{5}{3}} = 152 \times \frac{3}{5} = 91.2 \text{ s}$$​​