Question 954230
Let {{{ t }}} = his time in minutes 
for him to get to school on time
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(1) {{{ d = 40*( t + 5 ) }}}
(2) {{{ d = 60*( t - 3 ) }}}
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By substitution:
{{{ 40*( t + 5 ) = 60*( t - 3 ) }}}
{{{ 40t + 200 = 60t - 180 }}}
{{{ 20t = 380 }}}
{{{ t = 19 }}}
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(2) {{{ d = 60*( t - 3 ) }}}
(2) {{{ d = 60*( 19 - 3 ) }}}
(2) {{{ d = 60*16 }}}
(2) {{{ d = 960 }}}
Jimmy's house is 960 m from the school
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check:
(1) {{{ d = 40*( t + 5 ) }}}
(1) {{{ 960 = 40*( 19 + 5 ) }}}
(1) {{{ 960 = 40*24 }}}
(1) {{{ 960 = 960 }}}
OK