document.write( "Question 362276: 41) The food marketing institute shows that 17% of households spend more than $100 per wee on groceries. Assume the population proportion is p=.17 and a simple random sample of 800 households will be selected from the population.
\n" ); document.write( "a) Show the sampling distribution of p, the sample proportion of households spending more than $100 per week on groceries.
\n" ); document.write( "b) What is the probability that the sample proportion will be with in plus or minus .02 of the population proportion?
\n" ); document.write( "c) Answer part (b) for a sample of 1600.
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Algebra.Com's Answer #258157 by stanbon(75887)\"\" \"About 
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The food marketing institute shows that 17% of households spend more than $100 per week on groceries. Assume the population proportion is p=.17 and a simple random sample of 800 households will be selected from the population.
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\n" ); document.write( "a) Show the sampling distribution of p, the sample proportion of households spending more than $100 per week on groceries.
\n" ); document.write( "The mean of the sample means = 0.17
\n" ); document.write( "The standard deviation of the sample means = sqrt[0.17*0.83/800]
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\n" ); document.write( "b) What is the probability that the sample proportion will be within plus or minus .02 of the population proportion?
\n" ); document.write( "z(0.19) = (0.19-0.17)/sqrt(0.17*0.83/800] = 1.5060
\n" ); document.write( "z(0.15) = -1.5060
\n" ); document.write( "P(0.15< p < 0.19) = P(-1.5060< z <1.5060) = 0.8679
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\n" ); document.write( "c) Answer part (b) for a sample of 1600.
\n" ); document.write( "Put 1600 in place of 800 in the calculations.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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