A crew can row a certain course up the stream in 84 minutes; they can row the same course down stream in 9 minutes less than they can row it in still water. How long would they take to row down with the stream Choose the correct option:
A) 45 or 23 minutes
B) 63 or 12 minutes
C) 60 minutes
D) 19 minutes
E) 25 minutes
speed of a crew in still water = 1/2 ( speed upstream + speed downstream)   approximating this for time,   t = 1/2(84+ (t-9))   giving t = 66 close to 63 or 12 minutes   ANSWER:63 or 12 minutes
<result>B</result>
A crew can row a certain course up the stream in 84 minutes; they can row the same course down stream in 9 minutes less than they can row it in still water. How long would they take to row down with the stream