Question 1059311
Let {{{ c }}} = the rate of the current in hrs
Let {{{ t }}} = the time in hrs to go either
downstream or upstream
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Going downstream:
(1) {{{ 16 = ( 18 + c )*t }}}
Going upstream:
(2) {{{ 8 = ( 18 - c )*t }}}
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(1) {{{ t = 16 / ( 18 + c ) }}}
Plug (1) into (2)
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(2) {{{ 8 = ( 18 - c )*( 16 / ( 18 + c ) ) }}}
(2) {{{ 8*( 18 + c ) = 16*( 18 - c ) }}}
(2) {{{ 144 + 8c = 288 - 16c }}}
(2) {{{ 24c = 144 }}}
(2) {{{ c = 6 }}}
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The rate of the current is 6 mi/hr