Question 1016904
Convert all minutes to hours
{{{ 40/60 = 2/3 }}} hrs
{{{ 12/60 = 1/5 }}} hrs
Let {{{ r }}} = her average biking rate
Let {{{ d }}} = distance in miles to train station
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Equation for walking:
(1) {{{ d = ( r-7 )*(2/3) }}}
Equation for biking:
(2) {{{ d = r*(1/5) }}}
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{{{ ( r-7 )*(2/3) = r*(1/5) }}}
Multiply both sides by {{{ 15 }}}
{{{  10*( r - 7 ) = 3r }}}
{{{ 10r - 70 = 3r }}}
{{{ 7r = 70 }}}
{{{ r = 10 }}}
and
{{{ r - 7 = 3 }}}
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(2) {{{ d = r*(1/5) }}}
(2) {{{ d =10*(1/5) }}}
(2) {{{ d = 2 }}}
and
(1) {{{ d = ( r-7 )*(2/3) }}}
(1) {{{ d =3*(2/3) }}}
(1) {{{ d = 2 }}}
The distance to the train station is 2 mi