A man can swim in still water at 7.5 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?
Choose the correct choice: A) 1.7 B) 1.4 C) 2.5 D) 1.5 E) 1.1
M = 7.5   S = x   DS = 7.5 + x   US = 7.5 + x   7.5 + x = (7.5 - x)2   7.5 + x = 15 -2x   3x = 7.5   x = 2.5   Answer: 2.5
<result>C</result>
A man can swim in still water at 7.5 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?