In 1965 a nationwide survey revealed that U.S. grade school children spent an average of 8.4 hours per week doing homework. Assume the distribution of homework times is normal. Last year a sample of 56 students were given the same survey. For this sample, the average number of homework hours was 7.5 hours with a standard deviation of 2.1 hours. Do these data indicate a decrease in the amount of homework hours for American grade school children? Let α = 0.10. Show all seven steps.

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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.