Question 838880
It looks like you want the speed of the current
Let {{{ c }}} = the speed of the current and
the distance he rows
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Rowing downstream:
(1) {{{ d = ( 5 + c )*( 17/60 ) }}}
Rowing upstream:
(2) {{{ d = ( 5 - c )*( 23/60 ) }}}
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Substitute (1) into (2)
{{{  ( 5 + c )*( 17/60 ) = ( 5 - c )*( 23/60 ) }}}
Multiply both sides by {{{ 60 }}}
{{{  ( 5 + c )*17 = ( 5 - c )*23 }}}
{{{ 85 + 17c = 115 - 23c }}}
{{{ 40c = 30 }}}
{{{ c = 3/4 }}}
The speed of the current is 3/4 mi/hr
check:
(1) {{{ d = ( 5 + .75 )*( 17/60 ) 
(1) {{{ d = 5.75*.28333 }}}
(1) {{{ d = 1.629 }}}
and
(2) {{{ d = ( 5 - .75 )*( 23/60 ) }}}
(2) {{{ d = 4.25*.38333 }}}
(2) {{{ d = 1.629 }}}
The one-way distance he rows is 1.629 mi