Question 247651
There are 10 people, so there are 10 ways you could pick the first person.  Those are the possibilities.  Two of them are married, so the chance that you pick either one of the married couple is 2/10 = 1/5 or 20%.
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Now that you have picked one member of the married couple, there are 9 ways you can pick the next person.  But only 1 of those is the spouse.  So the probability is 1/9.
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So the chance you pick the couple = 1/5 * 1/9 = 1/45
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As a check, you can determine the number of combinations of 2 people from a set of 10.  That defines the number of possibilities.  
{{{10!/(2!*8!)}}}
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{{{(10*9*8!)/(2! * 8!)}}}
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The 8! terms cancel.  So we have {{{(10*9)/2 = 45}}}.  There is only 1 way you pick the couple.  1/45.
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