SOLUTION: A boat takes 2/3 as much time to travel downstream as to return. If the rate of the current is 8 kph, what is the rate of the boat in still water?

Question 815697: A boat takes 2/3 as much time to travel downstream as to return. If the rate of the current is 8 kph, what is the rate of the boat in still water?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
s = d / t
t = d / s
---
w = 8 kph
---
d/(b + w) = (2/3)d/(b - w)
1/(b + w) = (2/3)/(b - w)
1/(b + w) - (2/3)/(b - w) = 0
(b - w)/(b + w)(b - w) - (2/3)(b + w)/(b + w)(b - w) = 0
( (b - w) - (2/3)(b + w) ) = 0(b + w)(b - w)
b - w - (2/3)b - (2/3)w = 0
(3/3)b - (2/3)b - (2/3)w - (3/3)w = 0
(1/3)b - (5/3)w = 0
(1/3)b - (5/3)8 = 0
b = (5/3)8(3/1)
b = (5)8
---
b = 40 kph
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Convert fractions, decimals, and percents:
https://sooeet.com/math/fraction-decimal-percent.php
---
Calculate and graph the linear regression of any data set:
https://sooeet.com/math/linear-regression.php
RELATED QUESTIONS
A boat takes 2/3 as much time to travel downstream as to return. If the rate of the... (answered by TimothyLamb)

A boat takes 2/3 as much time to travel downstream as to its return. If the rate of the... (answered by ikleyn,greenestamps)

a boat takes 2/3 as much time to travel downstream from c to d,as to return.if the rate... (answered by ewatrrr)

A boat takes 3 hours to travel 108 km upstream the return trip downstream takes 2 hours.... (answered by TimothyLamb)

in still water, a boat averages 7 mph. it takes the same amount of time to travel 20... (answered by ankor@dixie-net.com)

In still water, a boat averages 8 miles per hour. It takes the same amount of time to... (answered by lwsshak3)

In still water, a boat averages 15 miles per hour. It takes the same amount of time to... (answered by texttutoring)

In still water, a boat averages 8 miles per hour. It takes the same amount of time to (answered by josgarithmetic)

A motorboat takes 3 hours to travel 144 mi going upstream. The return trip takes 2... (answered by Alan3354,richwmiller)