Question 310774
Let {{{s}}} = the rate in still water
Let {{{r}}} = the rate of the river
given:
Rate rowing downstream = {{{48/4 = 12}}} km/hr
Time to row upstream = {{{6}}} hrs
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Rowing downstream:
{{{48 = 12*t[d]}}}
{{{t[d] = 4}}} hrs
{{{48 = (s + r)*4}}}
Rowing upstream:
{{{48 = (s - r)*6}}}
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{{{4s + 4r = 6s - 6r}}}
{{{2s = 10r}}}
{{{s = 5r}}}
and, since
{{{48 = (s + r)*4}}}
{{{s + r = 12}}}
{{{5r + r = 12}}}
{{{6r = 12}}}
{{{r = 2}}}
and
{{{s = 5r}}}
{{{s = 10}}}
The rate the team rows in still water is 10 km/hr
The rate of the river is 2 km/hr