document.write( "Question 328479: 5. (a) A production process comprises of two separate processes, moulding and assembly. It is known that the probability of a defect occurring in both processes is 0.03 and the probability of a defect occurring in the assembly process is 0.2. \r
\n" ); document.write( "\n" ); document.write( "(i) If it is assumed that the occurrence of a defect is independent of the process, calculate the probability of a defect occurring in either process.\r
\n" ); document.write( "\n" ); document.write( "(ii) Calculate the probability that an item will not contain a defect.\r
\n" ); document.write( "\n" ); document.write( "(iii) If a sample of three items are selected at random from the production output, what is the probability that at least one of them will have a defect?
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Algebra.Com's Answer #235403 by stanbon(75887)\"\" \"About 
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5. (a) A production process comprises of two separate processes, moulding and assembly.
\n" ); document.write( "It is known that the probability of a defect occurring in both processes is 0.03 and the probability of a defect occurring in the assembly process is 0.2
\n" ); document.write( "P(mould and assemb) = 0.03
\n" ); document.write( "P(assemb) = 0.2
\n" ); document.write( "Therefore P(mould) = 0.03/0.2 = 0.15
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\n" ); document.write( "(i) If it is assumed that the occurrence of a moulding defect is independent of the defect in the assemply process, calculate the probability of a defect occurring in either process.
\n" ); document.write( "P(mould OR assemb)= P(mould) + P(assemb) - P(mould AND assemb)
\n" ); document.write( "= 0.15+0.2 - 0.03 = 0.32
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\n" ); document.write( "(ii) Calculate the probability that an item will not contain a defect.
\n" ); document.write( "P(no defect) = 1-[P(m OR p)+P(m AND p)] = 1-[0.32+0.03] = 0.65
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\n" ); document.write( "(iii) If a sample of three items are selected at random from the production output, what is the probability that at least one of them will have a defect?
\n" ); document.write( "0.65^3 = 0.2746
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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