Question 927012
Let {{{ t }}} = time in hrs  spent in canoe
{{{ 12 - t }}} = time in hrs spent on bicycle
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{{{ d }}} = distance in miles traveled by canoe
{{{ 226 - d }}} = distance traveled by bicycle
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In canoe:
(1) {{{ d = 8t }}}
On bicycle:
(2) {{{ 226 - d = 21*( 12 - t ) }}}
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Substitute (1) into (2)
(2) {{{ 226 - 8t = 21*( 12 - t ) }}}
(2) {{{ 226 - 8t = 252 - 21t }}}
(2) {{{ 13t = 252 - 226 }}}
(2) {{{ 13t = 26 }}}
(2) {{{ t = 2 }}}
and
{{{ 12 - t = 10 }}}
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2 hrs was spent in the canoe
10 hrs was spent on bicycle
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check:
(2) {{{ 226 - d = 21*( 12 - t ) }}}
(2) {{{ 226 - d = 21*( 12 - 2 ) }}}
(2) {{{ 226 - d = 210 }}}
(2) {{{ d = 16 }}}
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(1) {{{ d = 8t }}}
(1) {{{ d = 8*2 }}}
(1) {{{ d = 16 }}}
OK