Question 888146
Let {{{ c }}} = the rate of the current
{{{ 4 + c }}} = man's rate going downstream
{{{ 4 - c }}} = man's rate going upstream
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{{{ 4 + c = 3*( 4 - c ) }}}
{{{ 4 + c = 12 - 3c }}}
{{{ 4c = 8 }}}
{{{ c = 2 }}}
The rate of the current is 2 mi/hr
check:
{{{ 4 + c = 3*( 4 - c ) }}}
{{{ 4 + 2 = 3*( 4 - 2 ) }}}
{{{ 6 = 3*2 }}}
{{{ 6 = 6 }}}
OK