Is there a shortcut to solve this?

Sahil 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.

(a) 45 or 23 minutes



(c) 60 minutes

(d) 19 minutes

(b) 63 or 12 minutes