document.write( "Question 1090293: A bag contains 4 red, 2 white and3 blue balls. If two balls are chosen at rand without replacement, find the probability that the balls are of the same colour. \n" ); document.write( "

Algebra.Com's Answer #704744 by ikleyn(52864) $\"\"$ $\"About$

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\n" ); document.write( "A bag contains 4 red, 2 white and 3 blue balls. If two balls are chosen at $\"highlight%28cross%28rand%29%29\"$ random without replacement,
\n" ); document.write( "find the probability that the balls are of the same $\"highlight%28cross%28colour%29%29\"$ color.
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document.write( "There are   =  =  = 6 combinations to choose two red balls.\r\n" );
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document.write( "There are   = 1 combination to choose two white balls.\r\n" );
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document.write( "There are   =  =  = 3 combinations to choose two blue balls.\r\n" );
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document.write( "Thus there are 6 + 1 + 3 = 10 combinations to choose two balls of the same color.\r\n" );
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document.write( "The entire space of events is   =  =  =  = 36 combinations to choose two balls from the bag containing 4 + 2 + 3 = 9 balls.\r\n" );
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document.write( "Therefore, the probability that the balls are of the same color is   = .\r\n" );
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\n" ); document.write( "\n" ); document.write( "About combinations and about these magic numbers $\"C%5Bn%5D%5Ek\"$ you can read from the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Introduction to Combinations\r
\n" ); document.write( "\n" ); document.write( "    - PROOF of the formula on the number of Combinations\r
\n" ); document.write( "\n" ); document.write( "    - Problems on Combinations\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Combinatorics: Combinations and permutations\". \r
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\n" ); document.write( "\n" ); document.write( "Also see the lesson\r
\n" ); document.write( "\n" ); document.write( "    - Elementary Probability problems related to combinations \r
\n" ); document.write( "\n" ); document.write( "from the same online textbook.\r
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