Question 512012
Let {{{d}}} = distance Lem has to go
{{{ d - 50 }}} = distance Uel has to go
Let {{{ t}}} = time that it takes Lem to catch Uel
given:
For Uel:
(1) {{{ d - 50 = 6t }}}
For Lem:
(2) {{{ d = 10t }}}
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Substitute (2) into (1)
(1) {{{ 10t - 50 = 6t }}}
(1) {{{ 4t = 50 }}}
(1) {{{ t = 12.5 }}} sec
check:
(1) {{{ d - 50 = 6*12.5 }}}
(1) {{{ d - 50 = 75  }}}
(1) {{{ d = 125 }}} m
and
(2) {{{ d = 10*12.5 }}}
(2) {{{ d = 125 }}} m
OK