SOLUTION: Manuel has a boat that can move at a speed of 15 km/h in still water. He rides 140 km downstream in a river in the same time it takes to ride 35 km upstream. What is the speed of t
Algebra.Com
Question 807432: Manuel has a boat that can move at a speed of 15 km/h in still water. He rides 140 km downstream in a river in the same time it takes to ride 35 km upstream. What is the speed of the river?
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
Boat speed = 15 km/h
current speed = x km/h
speed against current 15 - x
speed with current 15 + x
Distance against current 35 miles
Distance with current 140 miles
t=d/r time against = time with current -
35 / ( 15 - x )= 140 / ( 15 + x )
35 ( 15 + x )= 140 ( 15 -x )
525 + 35 x = 2100 - -140 x
140 x 35 x 2100 + -525
175 x = 1575
/ 175
x = 9 km/h current speed
RELATED QUESTIONS
a paddle boat can move at the speed of 20 km/h in still water. the boat is paddled 12km... (answered by mananth)
A paddle boat can move at a speed of 12 km/h in still water. The boat is paddled 6 km... (answered by checkley71,TakeATuition.com)
A paddle boat can move at a speed of 20 km/h in still water. The boat is paddled 14 km... (answered by mananth)
A paddle boat can move at a speed of 2 km/h in still water. The boat is paddled 6... (answered by josgarithmetic)
A paddle boat can move at a speed of 2 km/h in still water. The boat is paddled 14
(answered by josgarithmetic,MathTherapy)
A paddle boat can move at a speed of 8 km/h in still water. The boat is paddled 4 km... (answered by josgarithmetic,ikleyn)
A boat can travel at a speed of 15 kph in still water. The boat travels 40 km downstream... (answered by mananth)
A paddleboat can move at a speed of 20 km/h in still water. The boat is paddled 6 km... (answered by josmiceli)
A paddleboat can move at a speed of 6 km/h in still water. The boat is paddled... (answered by ikleyn)