The speed at which a man can row a boat in still water is 150 kmph. If he rows downstream, where the speed of current is 48 kmph, what time will he take to cover 390 metres?
Choose the correct choice from the following answers.
A) 10 B) 11 C) 12 D) 13 E) 14
Speed of the boat downstream = 150 + 48= 
<gadget id="calculator">150 + 48</gadget>
<output>198</output>
198 kmph= 198 * 5/18 = 30 m/s   Hence time taken to cover 390 m = 390/30= 
<gadget id="calculator">390/30</gadget>
<output>13</output>
13 seconds. Answer: 13
<result>D</result>
The speed at which a man can row a boat in still water is 150 kmph. If he rows downstream, where the speed of current is 48 kmph, what time will he take to cover 390 metres?