Question 959292
Let {{{ t }}} = the time in hours for both bikers
Ler {{{ s }}} = Seth's speed in mi/hr
Ryan's equation:
(1) {{{ 10 = ( s+3 )*t }}}
Seth's equation:
(2) {{{ 7.5 = s*t }}}
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(2) {{{ t = 7.5/s }}}
Substitute (2) into (1)
(1) {{{ 10 = ( s+3 )*( 7.5/s ) }}}
(1) {{{ 10 = 7.5 + 22.5/s }}}
(1) {{{ 10s = 7.5s + 22.5 }}}
(1) {{{ 2.5s = 22.5 }}}
(1) {{{ s = 9 }}}
and
{{{ s +3 = 12 }}}
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Seth's speed is 9 mi/hr
Ryan's speed is 12 mi/hr
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check:
(1) {{{ 10 = ( 9+3 )*t }}}
(1) {{{ 10 = 12t }}}
(1) {{{ t = 5/6 }}} hrs
and
(2) {{{ 7.5 = 9t }}}
(2) {{{ t = 7.5/9 }}}
(2) {{{ t = 5/6 }}}
OK