A boat travels 40 km downstream in 8 hours and 24 km upstream in 12 hours. Find the speed of the boat in still water and the speed of the water current.	Choose the correct choice:
A) 8 km/hr, 1 km/hr
B) 3.5 km/hr, 1.5 km/hr
C) 1 km/hr, 6 km/hr
D) 2 km/hr, 1 km/hr
E) 4 km/hr, 1 km/hr
Downstream speed=40km/8hrs   =5 kmph   upstream speed40  /8= 
<gadget id="calculator">40  /8</gadget>
<output>5</output>
5 kmph   upstream speed=24km/12hrs   =2 kmph   speed of boat24  /12= 
<gadget id="calculator">24  /12</gadget>
<output>2</output>
2 kmph   speed of boat=avg of downstream and upstream speeds   speed of boat=(5+2)/2= 
<gadget id="calculator">(5+2)/2</gadget>
<output>7/2 = around 3.5</output>
3.5kmph.   current speed=half of the difference of downstream and upstream speeds   currend speed=(5-2)/2= 
<gadget id="calculator">(5-2)/2</gadget>
<output>3/2 = around 1.5</output>
1.5kmph   ans is 3.5km/hr,1.5km/hr   ANSWER:3.5 km/hr, 1.5 km/hr
<result>B</result>
A boat travels 40 km downstream in 8 hours and 24 km upstream in 12 hours. Find the speed of the boat in still water and the speed of the water current.