Question 1101746
Let {{{ d  }}} = the one-way distance she traveled in km
Let {{{ t }}} - her time in hrs spent walking
{{{ 21 - t }}} = her time in hrs spent riding on the bus
(1) {{{ d = 5t }}}
(2) {{{ d = 30*( 21 - t ) }}}
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{{{ 5t = 30*( 21 - t ) }}}
{{{ 5t = 630 - 30t }}}
{{{ 35t = 630 }}}
{{{ t = 18 }}}
and
{{{ 21 - t = 21 - 18 }}}
{{{ 21 - t = 3 }}}
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She walked for 18 hrs and
rode the bus for 3 hrs
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check:
(1) {{{ d = 5t }}}
(1) {{{ d = 5*18 }}}
(1) {{{ d = 90 }}} km
and
(2) {{{ d = 30*( 21 - t ) }}}
(2) {{{ d = 630 - 30t }}}
(2) {{{ d = 630 - 30*18 }}}
(2) {{{ d = 630 - 540 }}}
(2) {{{ d = 90 }}} km
OK