Question #53981

1 Answer
Nov 15, 2017

Laura and Brent paddle at 1.75 miles per hour in still water

Explanation:

Assume that Laura and Brent paddle at a constant speed

let #x# be their paddling speed
let #y# be the speed of the river

up-river
#6/4 = x-y#

down-river
#6/3 = x+y#

to get rid of the #y# term add the two equations together
#3.5 = 2x#

and rearrange
#x = 1.75#