document.write( "Question 1132287: Seven of 12 employees of a corporation are men. Suppose that 4 employees are
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\n" ); document.write( "contain: a) exactly 3 men? B) at least 3 men? C) what is the probability
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Algebra.Com's Answer #749267 by Edwin McCravy(20062)\"\" \"About 
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Seven of 12 employees of a corporation are men. Suppose that 4 employees are
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document.write( "That's 7 men employees plus 5 women employees = 12 employees\r\n" );
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document.write( "That's 3 men and 1 woman.\r\n" );
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document.write( "(7 men CHOOSE 3)∙(5 women CHOOSE 1) = (7C3)∙(5C1) = (35)∙(5) = 175  \r\n" );
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document.write( "b) at least 3 men? \r\n" );
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document.write( "That's the number with exactly 3 men PLUS the number with exactly 4 men.\r\n" );
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document.write( "We have already found that the number with exactly 3 men is 175.\r\n" );
document.write( "So we need to add the number with exactly 4 men (and no women).\r\n" );
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document.write( "175 + (7 men CHOOSE 4) = 175 + 35 = 210 \r\n" );
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\n" ); document.write( "C) what is the probability that a random selection will contain exactly 3 men?
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document.write( "That's 175 ways (from part a) out of (12 choose 4) = 175/(12C4) = \r\n" );
document.write( "175/495 = 35/99\r\n" );
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document.write( "Edwin
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