A man can swim in still water at 6 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is? Choose the correct choice from the following options.
A) 2 B) 1.4 C) 1.1 D) 1.5 E) 1.9
M = 6   S = x   6 + x = (4.5 - x)2   6 + x = 12 -2x   3x = 6   x = 2   2nswer:2
<result>A</result>
A man can swim in still water at 6 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?