Questions from Statistics Principles


Q: The daily number of kayaks sold, X, at a water

The daily number of kayaks sold, X, at a water sports store has the probability distribution (a) Find the expected number of kayaks sold in a day. (b) Find the standard deviation of the number of kay...

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Q: Suppose packages of cream cheese coming from an automated processor have weights

Suppose packages of cream cheese coming from an automated processor have weights that are normally distributed. For one day's production run, the mean is 8.2 ounces and the standard deviation is 0.1 o...

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Q: An experiment was conducted to study whether cloud seeding reduces the occurrences

An experiment was conducted to study whether cloud seeding reduces the occurrences of h ail. At a hail-prone geographical area, seeding was done on 50 stormy days and another 155 stormy days were also...

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Q: Present the result that 158 male babies were born to 363 parents

Present the result that 158 male babies were born to 363 parents both of whom smoke. The same study found that 2685 male babies were born to 5045 parents, neither of which smoked. Obtain a 95% confide...

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Q: 1. If a fixed number c is added to all measurements

1. If a fixed number c is added to all measurements in a data set, then the mean of the new measurements is c + (the original mean). 2. If all measurements in a data set are multiplied by a fixed nu...

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Q: A study ( courtesy of R. Golubjatnikov) is undertaken to

A study ( courtesy of R. Golubjatnikov) is undertaken to compare the rates of prevalence of CF antibody to parainfluenza I virus among boys and girls in the age group 5 to 9 years. Among 113 boys test...

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Q: We illustrate the MINITAB commands and output for the two-sample

We illustrate the MINITAB commands and output for the two-sample t t est. The approximate t test is performed if you don't click Assume equal variances. (a) From the output, what is the conclusion to...

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Q: Refer to the alligator data in the Data Bank. Using the

Refer to the alligator data in the Data Bank. Using the data on testosterone x 4 for male alligators, compare the means for the two lake regions. (a) Should you pool the variances with these data? (...

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Q: Use the approximate t-test to test the equality of means

Use the approximate t-test to test the equality of means with the two samples x: 7 15 6 12 y: 12 8 6 11 8 (a) Calculate the sample means and variances by hand and use calculator to evaluate d.f and t....

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Q: Refer to the marine growth of salmon data in the Data Bank

Refer to the marine growth of salmon data in the Data Bank. Compare the mean growth of males and females by obtaining a 95% confidence interval for the difference of means and also test equality versu...

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