Question 1109022
Let {{{ d }}} = the one-way distance
Let {{{ t }}} = time in hrs for the trip at {{{ 80 }}} mi/hr
(1) {{{ d = 80t }}}
(2) {{{ d = 70*( t + 1/7 ) }}}
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{{{ 80t = 70*( t + 1/7 ) }}}
{{{ 80t = 70t + 10 }}}
{{{ 10t = 10 }}}
{{{ t = 1 }}}
and
(1) {{{ d = 80*1 }}}
The appointment was 80 mi away
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check:
(2) {{{ d = 70*( 1 + 1/7 ) }}}
(2) {{{ d = 70*( 8/7 ) }}}
(2) {{{ d = 80 }}} 
OK