The United States Census Bureau determined that the mean number of children in an American household is 1.86. Polls of 15 households were conducted in a certain city. 1) What is the number of degrees of freedom? 2) A poll of 15 households had a sample mean of 3.26 children and a sample standard deviation of 2.12 children. What is the -statistic? 3) What is the probability of finding 15 households with a sample mean of 3.26 children or less? 4) A different poll of 15 households had a sample mean of 2,72 children and a sample standard deviation of 2.12 children. What is the -statistic? 5) What is the probability of finding 15 households with a sample mean between 2.72 and 3.27 children and a standard deviation of 2.12?
Added by William M.
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Step 1: Degrees of freedom = n − 1 = 15 − 1 = 14. Show more…
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