Question 1048489
Let {{{ d }}} = distance in miles traveled on
the straight road
{{{ 250 - d }}} = distance in miles  traveled on the
winding road
Let {{{ s }}} = speed in mi/hr on winding road
{{{ s + 20 }}} = speed in mi/hr on straight road
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Equation for straight road:
(1) {{{ d = ( s+20 )*2 }}}
Equation for winding road:
(2) {{{ 250 - d = s*3 }}}
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Substitute (1) into (2)
(2) {{{ 250 - 2s - 40 = s*3 }}}
(2) {{{ 5s = 210 }}}
(2) {{{ s = 42 }}}
The speed on the winding road was 42 mi/hr
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check:
(1) {{{ d = ( 42 + 20 )*2 }}}
(1) {{{ d = 124 }}} mi
and
(2) {{{ 250 - d = 3*42 }}}
(2) {{{ d = 250 - 126 }}}
(2) {{{ d = 124 }}} mi
OK