Question 858477
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*[tex \LARGE d\ =\ rt] hence *[tex \LARGE r\ =\ \frac{d}{t}]


If *[tex \LARGE r_s] is the rate in still water and *[tex \LARGE r_c] is the rate of the current, then the rate of the boat relative to the shoreline for the upstream trip would be *[tex \LARGE r_s\ -\ r_c] whereas the rate of the boat relative to the shoreline for the downstream trip would be *[tex \LARGE r_s\ +\ r_c].  Then, using *[tex \LARGE r\ =\ \frac{d}{t}], the upstream trip could be described as:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r_s\ -\ r_c\ =\ \frac{8}{1}] kmph.


While the downstream trip could be described as:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r_s\ +\ r_c\ =\ \frac{8}{2/3}\ =\ 12] kmph.


Solve the system of equations for *[tex \LARGE r_s] and *[tex \LARGE r_c]


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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