Question 912719
Uniform Rates for Travel, <b>RT=D</b> rate time distance


Let r be the rate Gertude would row if no river current
Let c be the rate of the river, the rate of flow of the river current


_________________rate________time__________distance
DOWNSTREAM_______r+c____________4_____________24
UPSTREAM_________2r-c___________4_____________24


Note very carefully, "the rate of the boat in still water was doubled".