Question 497590
Let {{{c}}} = the speed of the current
Let {{{ b}}} = the speed of the boat in still water
Going downriver, the boat travels at {{{ b + c }}} mi/hr
Going upriver, the boat travels at {{{ b - c }}} mi/hr
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given:
going downriver,
(1) {{{ b + c = 10 }}} mi/hr
going upriver,,
(2) {{{ b - c = 2 }}} mi/hr
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(1) {{{ c = 10 - b }}}
Substitute this into (2)
(2) {{{ b - ( 10 - b ) = 2 }}}
(2) {{{ b - 10 + b = 2 }}}
(2) {{{ 2b = 12 }}}
(2) {{{ b = 6 }}}
The speed of the boat if there is no current is 6 mi/hr