document.write( "Question 1116679: the result of an examinatio. given to a class on three person A,B,C are :40%failed in paper A ;30 %failed in B;25%failed in paper C .15%failed in paper A and B;12%failed in B and C both;10% failed i. A and C ;and 3%failed in all three A,B and C.whag is the probability of a randomly sl3cted candidates passing in all the three papers? \n" ); document.write( "

Algebra.Com's Answer #731578 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Let me re-tell the problem in this equivalent way:\r
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document.write( "    Of 100 students, 40 failed in A;   30 failed in B;   25 failed in C;\r\n" );
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document.write( "                     15 failed in AB;  12 failed in BC;  10 failed in AC;\r\n" );
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document.write( "                      3 failed in ABC.\r\n" );
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document.write( "    How many students passed in all three papers ?\r\n" );
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document.write( "The number of those who failed at least in one of A, B and/or C is\r\n" );
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document.write( "    40 + 30 + 25 - 15 - 12 - 10 + 3 = 61.       (*)\r\n" );
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document.write( "The rest, 100-61 = 39 passed all three papers.\r\n" );
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document.write( "So,    of the class students,  or 39%, passed all three articles.\r\n" );
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\n" ); document.write( "If you want to know why and how the formula (*) works, the read these lessons\r
\n" ); document.write( "\n" ); document.write( " - Counting elements in sub-sets of a given finite set\r
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