document.write( "Question 1145345: In a shipment of 19 smartphones, 2 are defective. How many ways can a quality control inspector randomly test 5 smartphones, of which 2 are defective?\r
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Algebra.Com's Answer #766565 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "In each such a group, there are 3 good and 2 defective items.\r\n" );
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document.write( "So, the number of ways is equal  \"C%5B19-2%5D%5E3\" = \"C%5B17%5D%5E3\" = \"%2817%2A16%2A15%29%2F%281%2A2%2A3%29\" = 680.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is about COMBINATIONS.\r
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\n" ); document.write( "\n" ); document.write( "On Combinations,  see introductory lessons\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( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
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