document.write( "Question 969829: If there are 20 people waiting on the bus stop and you are driving your car, you stop and take with you 3 out of 20 on the bus stop (3 different people). But, it matters who sits on the front seat, and for the 2 other people who will seat on the back, ordering doesn't matter. How many combinations can be ?! \n" ); document.write( "

Algebra.Com's Answer #592622 by AnlytcPhil(1806) $\"\"$ $\"About$

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If there are 20 people waiting on the bus stop and you are driving your car, you
\n" ); document.write( "stop and take with you 3 out of 20 on the bus stop (3 different people). But, it
\n" ); document.write( "matters who sits on the front seat, and for the 2 other people who will seat on
\n" ); document.write( "the back, ordering doesn't matter. How many combinations can be ?!
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document.write( "You can pick the person to sit in the front seat 20 ways.  \r\n" );
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document.write( "For each of those 20 ways when you have picked the person to ride shotgun, there are \r\n" );
document.write( "19 people remaining from which to pick the pair to sit in the back.  That's: \r\n" );
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document.write( " ways for each of those 20 way to pick the shotgun rider.\r\n" );
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document.write( "Answer:  20*171 = 20C1*19C2 = 3420 ways.  \r\n" );
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document.write( "AnlytcPhil (stands for \"analytic philosophy\")

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