<PRE><B>Question 1153155</B>
Let {{{ x }}} = number that boarded at the terminal
After the 1st stop;
{{{ x/2 + 1 }}} are left
After 2nd stop:
{{{ ( 2/3 )*( x/2 + 1 ) + 1 }}} are left
{{{ ( 2/3 )*( x/2 + 1 ) + 1 = 15 }}}
{{{ x/3 + 2/3 + 1 = 15 }}}
{{{ x/3 + 5/3 = 15 }}}
Multiply both sides by {{{ 3 }}}
{{{ x + 5 = 45 }}}
{{{ x = 40 }}}
40 passengers left the terminal
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check:
1/2 got off, 1 got on
{{{ 40 - 20 + 1 = 21 }}} left
2/3 are left, 1 got on
{{{ 14 + 1 = 15 }}} are left
OK


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