document.write( "Question 469896: If the probability that a student in the statistic class will score grade A in the final exams is 0.72, determine the probability that out of 5 students selected random from the class at least 2 scored grade A? \n" ); document.write( "

Algebra.Com's Answer #322339 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "Note: The probability of x successes in n trials is: 
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document.write( "P = nCx*  where p and q are the probabilities of success and failure respectively. 
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document.write( "In this case p = .72 & q =.28
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document.write( "nCx = 
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document.write( "5 students selected
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document.write( "P(at least 2 scored an A) = 1 - P(0 scoring an A) -P(1 scoring an A)
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document.write( "                          = 1 - (.28)^5 - 5(.72)^1(.28)^4 = .9762 \n" );
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