A man rows downstream 30 km and upstream 18 km, taking 5 hours each time. What is the velocity of the stream (current)? Choose one:
A) 1.2 km/hr  B) 1.5 km/hr  C) 2.5 km/hr  D) 1.8 km/hr  E) None of these
30/(B+5) = 18/(B-5) = 5   ? B+5 = 6 km/hr   B - 5 = 3.6 km/hr   ? 5 = 1.2 km/hr   1.2 km/hrnswer: 1.2 km/hr.
<result>A</result>
A man rows downstream 30 km and upstream 18 km, taking 5 hours each time. What is the velocity of the stream (current)?