Exam 2: Organizing Data

A random sample of federal income tax returns is selected from the 2006 returns and a frequency histogram is constructed for the amount of federal income tax paid in 2006. The classes used to construct the histogram are $0 \leqslant 3000,3000 \leqslant 6000,6000 \leqslant 9000$ , and so on. What do you think the shape of the histogram will be? Explain your thinking.

A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogramfor the systolic blood pressure readings for those people aged between 25 and 40. Use the histogram to answer thequestion. The blood pressure readings were given to the nearest whole number. -Given that 200 people were aged between 25 and 40, approximately how many had a systolic blood pressure reading of 140 or higher?

Construct the requested histogram. -The table below shows the number of days off in a given year for 30 police detectives. Days off Frequency Relative frequency 0-under 2 10 0.333 2-under 4 1 0.033 4-under 6 1 0.233 6-under 8 7 0.233 8-under 10 1 0.033 10-under 12 4 0.133 Construct a relative-frequency histogram.

Classify the data as either discrete or continuous. -The average speed of cars passing a busy intersection between 4:30 P.M. and 6:30 P.M. on a Friday is 32.3 mi/h.

Complete the contingency table and use it to solve the problem. -The partially filled contingency table gives the frequencies of the data on age (in years)and sex from the residents of a retirement home. What is the relative frequency for persons in the age group 60-69?

A graphical display of a data set is given. State whether the distribution is (roughly)symmetric, right skewed, or leftskewed. -A relative frequency histogram for the sale prices of homes sold in one city during 2006 is shown below.

The temperature in Manhattan at 1 p.m. on New Year's Day was 34.1°F.

Provide an appropriate response. -The preschool children at Elmwood Elementary School were asked to name their favorite color. The results are listed below. Construct a frequency distribution and a relative frequency distribution. blue blue red green purple purple purple blue purple red purple red green green green red purple green purple yellow

A graphical display of a data set is given. Identify the overall shape of the distribution as (roughly)bell-shaped,triangular, uniform, reverse J-shaped, J-shaped, right skewed, left skewed, bimodal, or multimodal. -The dotplot shows heights of wrestlers.

Maria constructed the frequency distribution shown below. The data represent the heights of 60 randomly selected women. Height Frequency 54 -under 60 7 60-under 61 1 61-under 62 3 62-under 63 5 63-under 64 7 64-under 65 7 65-under 66 6 66 -under 72 24 She concluded from her frequency distribution that the heights 66, 67, 68, 69, 70, and 71 inches are the most common for women. What is wrong with her conclusion? How is her frequency distribution misleading and how could the table be improved?

A graphical display of a data set is given. Identify the overall shape of the distribution as (roughly)bell-shaped,triangular, uniform, reverse J-shaped, J-shaped, right skewed, left skewed, bimodal, or multimodal. -Two dice were rolled and the sum of the two numbers was recorded. This procedure was repeated 400 times. The results are shown in the relative frequency histogram below.

The possible values of a discrete variable always form a finite set.

Provide an appropriate response. -Explain in your own words the difference between a bar graph and a histogram. Give an example of data for which you might use a histogram and an example of data for which you might use a bar graph.

A graphical display of a data set is given. Identify the overall shape of the distribution as (roughly)bell-shaped,triangular, uniform, reverse J-shaped, J-shaped, right skewed, left skewed, bimodal, or multimodal. -A relative frequency histogram for the heights of a sample of adult women is shown below.

Classify the data as either discrete or continuous. -The following table shows the heights of the five tallest mountains in North America. Mountain Height (ft) Rank McKinley 20,320 1 Logan 19,850 2 Citlaltepec 18,700 3 St. Elias 18,008 4 Popocatepetl 17,930 5 What kind of data is given in the third column of the table?

Construct a stem-and-leaf diagram for the given data. -The normal monthly precipitation (in inches)for August is listed for 39 different U.S. cities. Construct an ordered stem-and-leaf diagram using two lines per stem. 3.5 1.6 2.4 3.7 4.1 3.9 1.0 3.6 1.7 0.4 3.2 4.2 4.1 4.2 3.4 3.7 2.2 1.5 4.2 3.4 2.7 4.0 2.0 0.8 3.6 3.7 0.4 3.7 2.0 3.6 3.8 1.2 4.0 3.1 0.5 3.9 0.1 3.5 3.4

Suppose that you wish to construct a stem-and-leaf diagram for the data set below. What would the stems be? 98 103 146 118 92 128 135 141 136 143 126 111 109 97 124 147 114 119 140 122 92 130 101 148 138 90 123

The bar graph below shows the average cost of renting a studio in one city in each of the years 2002 through 2006. By what percentage does the average price increase from 2002 to 2003? Obtain a truncated version of the graph by sliding a piece of paper over the bottom of the graph so that the bars start at 300. In the truncated graph, by what percentage does the price appear to increase from 2002 to 2003? Why is the truncated graph misleading?

Provide the requested response. -The table contains data from a study of daily study time for 40 students from Statistics 101. Construct an ogive from the data. Minutes on homework Number of students Relative frequency Cumulative relative frequency 0-under 15 2 0.05 0.05 15-under 30 4 0.10 0.15 30-under 45 8 0.20 0.35 45-under 60 18 0.45 0.80 60-under 75 4 0.10 0.90 75-under 90 4 0.10 1.00

A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogramfor the systolic blood pressure readings for those people aged between 25 and 40. Use the histogram to answer thequestion. The blood pressure readings were given to the nearest whole number. -Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading less than 120?