SOLUTION: A paddle boat can move at a speed of 4km/h in still water. The boat is paddled 121km downstream in a river in the same time it takes to go 6km upstream. What is the speed of the
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-> SOLUTION: A paddle boat can move at a speed of 4km/h in still water. The boat is paddled 121km downstream in a river in the same time it takes to go 6km upstream. What is the speed of the
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Question 379034: A paddle boat can move at a speed of 4km/h in still water. The boat is paddled 121km downstream in a river in the same time it takes to go 6km upstream. What is the speed of the river? The speed of the river is___km/h Answer by ewatrrr(24785) (Show Source):
Hi,
D = r*t OR t = D/r Question sets up an equality according to time it takes
Let c represent the rate of the current
cross mulitply to solve for x
121(4 - c) = 6(4 + c)
484 - 121c = 24 + 6c
460 = 127c
3.622kmph = c, the rate(speed) of the current
