Question 603473
let s=rate of stream (current) and c=rate of canoe


going downstream, the rates add ___ going upstream, the current is subtracted from the canoe
___ the calculations are in miles and hours


r = d / t


down ___ c + s = 40 / 6 = 20/3


up ___ c - s = [(3/5) * 40] / (3 * 6) = 4/3


adding the equations (eliminating s) ___ 2c = 24/3 ___ c = 4 mph


substituting (to find s) ___ (4) + s = 20/3 ___ s = 20/3 - 12/3 = 8/3 mph