document.write( "Question 1051583: Can someone help me with this problem:\r
\n" ); document.write( "\n" ); document.write( "In a certain production process, 25% of the items produced are found defective. It therefore requires through inspection of all the items produced before packing them for sale.\r
\n" ); document.write( "\n" ); document.write( "a) Develop a probability density function for the number of non-defective items in a day's production of n items.\r
\n" ); document.write( "\n" ); document.write( "b) Using your answer to a), determine the probability of getting at least 50 good items if 100 items are produced.
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Algebra.Com's Answer #667054 by rothauserc(4718)\"\" \"About 
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We use the binary probability distribution
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\n" ); document.write( "The probability of non-defective items is 1 - 0.25 = 0.75
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\n" ); document.write( "Probability(k items are non-defective) = nCk * p^k * q^(n-k), where n is number of items produced, k = number of non-defective items, p = probability of non-defective items, q = 1-p, nCk of the combination of n items taken k at a time
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\n" ); document.write( "a) Probability(k items are non-defective) = nCk * (0.75)^k * (0.25)^(n-k)
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\n" ); document.write( "b) Probability(at least 50 items are produced out of 100) is the summation of
\n" ); document.write( "the probabilities for 50, 51, 52, ..., 100
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\n" ); document.write( "Probability(at least 50 items are produced out of 100) = 0.999999
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