A boat goes 100 km downstream in 4 hours, and 75 Km upstream in 15 hours. The speed of the stream is?  Options
A) 10  B) 20  C) 25  D) 35  E) 15
100 --- 10 DS = 25   ? ---- 1   75 ---- 15 US = 5   ? ----- 1 S = (25 - 5)/2= 
<gadget id="calculator">(25 - 5)/2</gadget>
<output>10</output>
10 kmph.   10nswer:10
<result>A</result>
A boat goes 100 km downstream in 4 hours, and 75 Km upstream in 15 hours. The speed of the stream is?