How long will a boy take to run round a square field of side 40 meters, if he runs at the rate of 12km/hr?	Choose the most appropriate option.
A) 52sec  B) 48sec  C) 60sec  D) 25sec  E) 39sec
Speed = 12 km/hr = 12*5/18 = 10/3 m/sec   Distance = 40*4= 
<gadget id="calculator">40*4</gadget>
<output>160</output>
160m   Time taken= 160*3/10= 
<gadget id="calculator">160*3/10</gadget>
<output>48</output>
48sec   Answer is 48sec
<result>B</result>
How long will a boy take to run round a square field of side 40 meters, if he runs at the rate of 12km/hr?