A market research agency would like to estimate the proportion of Canadian households owning a personal computer. What minimum sample size will be required if they want to be 99% confident that the sample proportion will not differ from the true population proportion by more than 5%?

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A market research agency would like to estimate the proportion of Canadian households owning a personal computer. What minimum sample size will be required if they want to be 99% confident that the sample proportion will not differ from the true population proportion by more than 5%?

This is a two tailed test since we are testing whether sample proportion will not differ from the true population proportion

σp=standard error of proportion=√(pq/n)
The maximum value of standard error of proportion for any given value of n is when p=q=0.5

confidence ...

Solution Summary

The sample size required for estimating proportion with 99% confidence is calculated

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Standard Deviation (minutes)
Mean Observed Time (minutes)
1 0.60 2.40
2 0.20 1.50
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4 0.85 2.55
5 0.40 1.60
6 0.50 2.50
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b. Mode
c. Median
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Bea asks Brian the samplesize and the timeframe.
Brian responds, 140,000
Suppose the bank has one million customers in the USA (where the survey is conducted)
With a 95% confidence level and a margin of error of 3%, what would you recommend the minimum samplesize to be?
This is the minimum samplesize. In practi