A man can swim in still water at 3 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?  Choose one:
A) 1 B) 4.2 C) 5.3 D) 1.5 E) 5.2
M = 3   S = x   DS = 3 + x   US = 3 - x   3 + x = (3 - x)2   3 + x = 6 -2x   3x = 3   x = 1   1nswer:1
<result>A</result>
A man can swim in still water at 3 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?