document.write( "Question 1018796: In a box there are: 7 red books, 5 white books, and 6 blue books. Three books are selected.
\n" ); document.write( "How many different ways can this be done if the selection:
\n" ); document.write( "(a) must contain one of each color? c(7,1)c(5,1)c(6,1)= 210
\n" ); document.write( "(b) must contain all the same color? c(7,3)+c(5,3)+c(6,3)=65
\n" ); document.write( "(c) must include more than one color? I'm not sure how to set this up can you please guide me through?
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Algebra.Com's Answer #636451 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
C(18,3) = 816 is the number of ways of selecting any three books from the eighteen books without any restriction.
\n" ); document.write( "Now the number of ways in which one book of each color is selected is 210, which you have correctly determined. The complement of this event is the event in which AT LEAST one book of some color is selected.
\n" ); document.write( "Thus, the number of ways in which a selection includes more than one color is
\n" ); document.write( "816 - 210 = 606.
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