Question 712773
Let {{{ s }}} = the rate of the stream in mi/hr
Let {{{ b }}} = the rate of the boat with no current in mi/hr
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Going upstream, speed =
{{{ b - s }}} mi/hr
Going downstream, speed = 
{{{ b + s }}} mi/hr
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given: 
{{{ b + s = 96/3 }}}
{{{ b + s = 32 }}} mi/hr
and
{{{ b - s = 96/6 }}}
{{{ b - s = 16 }}} mi/hr
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Add the equations
{{{ b + s = 32 }}}
{{{ b - s = 16 }}} 
{{{ 2b = 48 }}}
{{{ b = 24 }}} 
and, since
{{{ b + s = 32 }}}
{{{ 24 + s = 32 }}}
{{{ s = 8 }}}
The speed of the stream is 8 mi/hr