Question 1154220
Let {{{ c }}} = the speed of the current in mi/hr
Let {{{ t }}} = time for both trips in mi/hr
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(1) {{{ 147 = ( 44 + c )*t }}}
(2) {{{ 117 = ( 44 - c )*t }}}
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Add the equations:
(1) {{{ 147 = 44t + c*t  }}}
(2) {{{ 117 = 44t - c*t  }}}
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{{{ 264 = 88t }}}
{{{ t = 3 }}}
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Plug this result back into (1) or (2)
(1) {{{ 147 = ( 44 + c )*t }}}
(1) {{{ 147 = ( 44 + c )*3 }}}
(1) {{{ 49 = 44 + c }}}
(1) {{{ c = 5 }}}
The current is 5 mi/hr
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check:
(2) {{{ 117 = ( 44 - c )*t }}}
(2) {{{ 117 = ( 44 - 5 )*3 }}}
(2) {{{ 117 = 39*3 }}}
(2) {{{ 117 = 117 }}}
OK