Question 775312
It is the same problem if one is standing still
and the other is moving away at the sum
of their speeds
Let {{{ s }}} = the speed of Sammy's bus in mi/hr
{{{ s - 20 }}} = the speed of Mike's bus in mi/hr
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{{{ 270 = ( s + s - 20 )*3 }}}
{{{ 270 = ( 2s - 20)*3 }}}
{{{ 270 = 6s - 60 }}}
{{{ 6s = 330 }}}
{{{ s = 55 }}}
{{{ s - 20 = 35 }}}
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Sammy's speed was 55 mi/hr
Mike's speed was 35 mi/hr
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check:
{{{ 270 = ( s + s - 20 )*3 }}}
{{{ 270 = ( 55 + 35 )*3 }}}
{{{ 270 = 90*3 }}}
{{{ 2780 = 270 }}}
OK