Page (3) 4. A recent survey of 2000 randomly selected households showed that 1750 of them had telephones. Assume that the sample is a simple random sample and the conditions for a binomial distribution are satisfied. (i)(2 points) Find the sample proportion of households that have a telephone. (ii)(3 points) Find a 95% confidence interval estimate for the population proportion of households with telephones. 5. Given are the diameters (in inches) of a simple random sample of marbles obtained from a factory. The sample standard deviation (to six decimal places) is 0.124925 inches. Assume that the population data are normally distributed. 0.18 0.24 0.30 0.47 0.43 0.17 0.47 0.23 0.44 0.39 0.48 0.17 0.23 0.19 0.45 0.43 (i)(3 points) Find a 90% confidence interval estimate for the population variance. (ii)(2 points) Find a 90% confidence interval estimate for the population standard deviation.
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Step 1: The sample proportion of households that have a telephone is the number of households with telephones divided by the total number of households in the sample. Show more…
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