Question 751913
Start a stop watch when you start running
Let {{{ t }}} = time in hrs for you to catch friend
Let {{{ d }}} = distance in ft you travel to catch friend
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Your equation:
(1) {{{ d = 12t }}}
Friend's equation:
(2) {{{ d - 1000 = 10t }}}
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Substitute (1) into (2)
(2) {{{ 12t - 1000 = 10t }}}
(2) {{{ 2t = 1000 }}}
(2) {{{ t = 500 }}} hrs
You will catch up in 500 hrs
check:
(1) {{{ d = 12*500 }}}
(1) {{{ d = 6000 }}} ft
and
(2) {{{ d - 1000 = 10*500 }}}
(2) {{{ d = 6000 }}} ft
OK
Note that {{{ 500/24 }}} = 20 days and 20 hrs