Questions from Statistics Principles

Q: The following table shows the age at inauguration of each U.

The following table shows the age at inauguration of each U.S. president. (a) Make a stem-and-leaf display with a double stem. (b) Find the median, Q1 and Q3.

Q: (a) Calculate x and s for the data 3 5

(a) Calculate x and s for the data 3 5 4 8. (b) Consider the data set 103 105 104 108, which is obtained by adding 100 to each number given in part. (a). Use your results from part (a) and the propert...

Q: The boxplot and summary statistics for data from 48 student on the

The boxplot and summary statistics for data from 48 student on the time spent, in minutes, at a social network site the previous day are (a) From the boxplot, determine whether or not the distribution...

Q: In a genetic study, a regular food was placed in each

In a genetic study, a regular food was placed in each of 20 vials and the number of flies of a particular genotype feeding on each vial recorded. The counts of flies were also recorded for another set...

Q: The data below were obtained from a detailed record of purchases of

The data below were obtained from a detailed record of purchases of toothpaste over several years ( courtesy of A. Banerjee). The usage times (in weeks) per ounce of toothpaste for a household taken f...

Q: To study how first-grade students utilize their time when assigned

To study how first-grade students utilize their time when assigned to a math task, a researcher observes 24 students and records their times off-task out of 20 minutes. For this data set, find: (a) Me...

Q: A data set has summary statistics x = 19.5

A data set has summary statistics x = 19.5 s = 6.0 Median = 16 .0 Q1 = 4.0 Q4 = 24.5 Approximately what proportion of the observations are (a) Below 24.5? (b) Above 4.0? (c) In the interval 7.5-31.5...

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

Refer to the alligator data of the Data Bank. Using the data on testosterone x4 from Lake Apopka: (a) Make separate dot plots for the male and female alligators. (b) Calculate the sample means for e...

Q: The 50 measurements of acid rain in Wisconsin, whose histogram is

The 50 measurements of acid rain in Wisconsin, whose histogram is given on page 18 are (a) Calculate the median and quartiles. (b) Find the 90th percentile. (c) Determine the mean and standard deviat...

Q: Refer to Exercise 2. 112. (a) Determine

Refer to Exercise 2. 112. (a) Determine the intervals x¯ ± s, x¯ ± 2 s, and x¯ ± 3 s. (b) What proportions of the measurements lie in those intervals? (c) Compare your findings with the empirical guid...