A boat can travel with a speed of 16 km/hr in still water. If the rate of stream is 5 km/hr, then find the time taken by the boat to cover distance of 84 km downstream. Pick:
A) 4 hours	B) 5 hours	C) 6 hours	D) 7 hours	E) 8 hours
Explanation:   It is very important to check, if the boat speed given is in still water or with water or against water. Because if we neglect it we will not reach on right answer. I just mentioned here because mostly mistakes in this chapter are of this kind only.   Lets see the question now.   Speed downstream = (16 + 5)= 
<gadget id="calculator">(16 + 5)</gadget>
<output>21</output>
21 kmph   Time= distance/speed = 84/21= 
<gadget id="calculator">84/21</gadget>
<output>4</output>
4 hours   4 hoursNSWER IS 4 hours
<result>A</result>
A boat can travel with a speed of 16 km/hr in still water. If the rate of stream is 5 km/hr, then find the time taken by the boat to cover distance of 84 km downstream.