A psychologist wants to test whether there is any difference in puzzle-solving abilities between boys and girls. Independent samples of 10 boys and 14 girls were chosen at random. The boys took a mean of 30 minutes to solve a certain puzzle with a standard deviation of 8 minutes. The girls took mean of 34 minutes to solve the same puzzle with a standard deviation of 5 minutes. Assume that the two populations of completion times are normally distributed and that the population variances are equal. Construct a 95% confidence interval for the difference u, - µ, between the mean puzzle-solving times for boys (u) and for girls (µ,). Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) What is the lower limit of the 95% confidence interval? What is the upper limit of the 95% confidence interval?

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A:

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.