document.write( "Question 995781: I need a guidance as to how to solve this problem.\r
\n" ); document.write( "\n" ); document.write( " Fifteen people are summoned to jury duty. 9 are women and 6 are men.
\n" ); document.write( "(a) In how many ways can 12 jurists be randomly selected out of the 15 people? Show work.
\n" ); document.write( "(b) In how many ways can 12 jurists be chosen, if 7 must be women and 5 must be men? Show work.
\n" ); document.write( "(c) If 12 jurists are randomly selected from the 15 people, what is the probability that 5 are men and 7 are women? Round answer to nearest ten-thousandth (4 places after decimal). Show work.
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Algebra.Com's Answer #614462 by ikleyn(52818)\"\" \"About 
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\n" ); document.write( " I need a guidance as to how to solve this problem.
\n" ); document.write( "Fifteen people are summoned to jury duty. 9 are women and 6 are men.
\n" ); document.write( "(a) In how many ways can 12 jurists be randomly selected out of the 15 people? Show work.
\n" ); document.write( "(b) In how many ways can 12 jurists be chosen, if 7 must be women and 5 must be men? Show work.
\n" ); document.write( "(c) If 12 jurists are randomly selected from the 15 people, what is the probability that 5 are men and 7 are women? Round answer to nearest ten-thousandth (4 places after decimal). Show work.
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\n" ); document.write( "\n" ); document.write( "(a)  In how many ways can  12  jurists be randomly selected out of  15  people?\r
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\n" ); document.write( "It is the standard conception of combinations.  Do you know it?  Are you familiar with it?  If not,  look in the lesson  Introduction to Combinations  in this site. \r
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\n" ); document.write( "\n" ); document.write( "The number in which  12  jurists can be randomly selected out of  15  people is the number of combinations of  15  things taken  12  at time: \r
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\n" ); document.write( "\n" ); document.write( "\"C%5B15%5D%5E12\" = \"15%21%2F%2812%21%2A3%21%29\" = \"%2815%2A14%2A13%29%2F%281%2A2%2A3%29\" = 5*7*13 = 455.\r
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\n" ); document.write( "\n" ); document.write( "(b)  In how many ways can  12  jurists be chosen, if  7  must be women and  5  must be men?\r
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\n" ); document.write( "\n" ); document.write( "7  jurists out of  9  women can be randomly chosen in  \"C%5B9%5D%5E7\" = \"9%21%2F%287%21%2A2%21%29\" = \"%289%2A8%29%2F%281%2A2%29\" = 9*4 = 36 ways. \r
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\n" ); document.write( "\n" ); document.write( "5  jurists out of  6  men can be randomly chosen in  \"C%5B6%5D%5E5\" = \"6%21%2F%285%21%2A1%21%29\" = \"6%2F1\" = 6 ways. \r
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\n" ); document.write( "\n" ); document.write( "Combining  36  ways for women with  6  ways for men  (they are independent!)  you obtain  36*6 = 216 ways.\r
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\n" ); document.write( "\n" ); document.write( "(c) If 12 jurists are randomly selected from the 15 people, what is the probability that 5 are men and 7 are women? \r
\n" ); document.write( "\n" ); document.write( "Round answer to nearest ten-thousandth (4 places after decimal).\r
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\n" ); document.write( "\n" ); document.write( "This probability is the ratio of that two numbers we obtained as answers to problems (a) and (b): \r
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\n" ); document.write( "\n" ); document.write( "Probability = \"216%2F455\" = 0.4747 (approx.)\r
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