Question 682872
Let {{{ d }}} = the distance in meters that the faster runner will
travel until they meet.
{{{ 100 - d }}} = the distance in meters  the slower runner will
travel until they meet
Let {{{ t }}} = time from when they are {{{ 100 }}} m apart
until they meet
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Equation for faster runner:
(1) {{{ d = 4.5t }}}
Equation for slower runner:
(2) {{{ 100 - d = 3.5t }}}
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Substitute (1) into (2)
(2) {{{ 100 - 4.5t = 3.5t }}} 
(2) {{{ 8t = 100 }}}
(2) {{{ t = 12.5 }}}
It will take the runners 12.5 hrs to meet
and
(1) {{{ d = 4.5t }}}
(1) {{{ d = 4.5*12.5 }}}
(1) {{{ d = 56.25 }}}
and
{{{ 100 - d = 100 - 56.25 }}}
{{{ 100 - d = 43.75 }}}
The faster runner runs 56.25 m
The slower runner runs 43.75 m
check:
(2) {{{ 100 - d = 3.5t }}}
(2) {{{ 100 - 56.25 = 3.5*12.5 }}}
(2) {{{ 43.75 = 43.75 }}}
OK