" x stands for the sum (the total) of the numbers

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1 June 3, 2009 Statistics on your calculator page 1 Statistics on your calculator Your calculator has many statistics features, found mostly under STAT and 2 nd Y= (STATPLOT). You used one of these features, LinReg (linear regression, or best-fit lines), earlier in the course. Today you ll learn about all the things your calculator can do when given a set of data. Entering, analyzing, and sorting a data set (A) You can enter a set of data by typing STAT ENTER (Edit) then typing the numbers into column L 1. For the example, use this set of numbers: {26, 40, 42, 5, 21, 26, 43, 47, 23, 9, 19, 27, 29, 12, 17, 24, 26, 14, 17, 25} (B) A command called 1-Var Stats displays many pieces of information about the data set in column L 1. The keys to press are STAT -> ENTER ENTER. You ll also need to press a few times to scroll down to see the last few numbers. Here are the things you ll see displayed that we ve studied. (There are also a few more numbers that we haven t discussed.) x stands for the mean (the average) " x stands for the sum (the total) of the numbers n tells how many numbers you entered (useful for checking) minx gives the minimum Q 1 gives the first quartile Med gives the median Q 3 gives the third quartile maxx gives the maximum (Note that the last five numbers are the five-number summary used when making a boxplot.) (C) The calculator can also sort your list of numbers. Give the command SortA(L 1 ) by pressing STAT 2 2 nd LIST ENTER ) ENTER. Then go back into Edit ( STAT ENTER) and you ll see the numbers you entered there have now been sorted. scroll down to see more

2 June 3, 2009 Statistics on your calculator page 2 Making boxplots and histograms (D) The calculator can make a boxplot of the data you typed in L 1. Press 2 nd Y= (STATPLOT), choose ENTER, then make the settings match what s shown in the first screenshot. To set the Type to boxplot, arrow down to Type: and then arrow right four times to the boxplot icon. (Even though this icon is in the 2 nd row under Type:, you get to it by arrowing right.) Next, press WINDOW and set the Xmin and Xmax for an interval that includes all of your numbers. For the example, try 0-to-50. Press GRAPH to see the boxplot. You can find out the five numbers used to make the boxplot by pressing TRACE then moving around with the arrow keys. (E) The calculator can also make a histogram (grouped bar graph). Press 2 nd Y= (STATPLOT), choose 1, then make the settings match what s shown in the first screenshot. Note the choice of type is the third one, that looks a bit like a histogram. One of the settings underneath WINDOW is critical. Xscl decides how wide the grouping intervals will be. For the example, Xscl=10 makes the groups begin from 0, 10, 20, 30, and 40. Press GRAPH to see the histogram. You can check the intervals of numbers that were used, and find out how many data values were in each interval, by pressing TRACE then moving around with the arrow keys. In the screenshot, it says there were 5 data values (n=5) that were 10 or greater, but less than 20.

3 June 3, 2009 Statistics on your calculator page 3 Problems 1. Here are the point scores of an NFL football team for each game of a season: 35, 31, 23, 34, 27, 34, 19, 28, 34, 20, 34, 24, 17, 14, 21, 37 Enter this data in the calculator, then use the calculator s features to answer the questions below. a. What was the average number of points scored in a game? b. What was the median number of points scored in a game? c. What was the total number of points scored in the season? d. Write the five-number summary (the five numbers used in a boxplot). e. Make a boxplot on your calculator. Sketch your screen below. f. Make a histogram on your calculator where the scores are grouped as shown below. Record how many scores are in each group, and fill in the screen picture. 0 score<5 5 score<10 10 score<15 15 score<20 20 score<25 25 score<30 30 score<35 35 score<40

4 June 3, 2009 Statistics on your calculator page 4 2. This table lists 21 Presidents of the United States and the number of years that they lived. Washington 67 Filmore 74 T. Roosevelt 60 J. Adams 90 Pierce 64 Taft 72 Jefferson 83 Buchanan 77 Wilson 67 Madison 85 Lincoln 56 Harding 57 Monroe 73 Johnson 66 Coolidge 60 J.Q. Adams 80 Grant 63 Hoover 90 Tyler 70 Garfield 49 Kennedy 46 Enter this data in the calculator, then use the calculator s features to answer the questions below. a. Make a list of the Presidents years lived, sorted from smallest to largest. Use the command SortA(L 1 ) to help you. b. Which of these Presidents lived the shortest and lived the longest? c. Which President(s) had the median number of years lived? d. What was the mean number of years lived? e. List all of the Presidents whose lives were shorter than average, in comparison to this list.

5 June 3, 2009 Statistics on your calculator page 5 (Continue using the data about Presidents from the previous page.) f. Make the five-number summary and a boxplot. Make sure your window is set so that all of the Presidents ages fit on the x-axis. Five number summary: (name the five quantities and give their number values) Boxplot: g. Redraw your calculator boxplot above the scale shown below. Label each of the five places on your boxplot with its name and its number. (example of a label: minimum 46 ) h. Choose an appropriate grouping for the Presidents ages, then make a histogram. What grouping did you use? Histogram: i. For the grouping you used when making the histogram, which group of ages contained the most Presidents? List the Presidents whose ages fell in that interval.

6 June 3, 2009 Statistics on your calculator page 6 3. The given stemplot shows the high temperature (in degrees Fahrenheit) recorded at Springfield Airport for each of the 30 days of November. a. Enter the temperature data in L 1 of your calculator as an ordinary list of numbers. b. Which was greater, the mean high temperature or the median high temperature? Show the numbers leading to your conclusion c. With the help of your calculator, make a boxplot representing the high temperatures. Transfer the boxplot onto your paper using the scale given below, and label the boxplot with the numbers used d. Make a histogram on your calculator of the temperatures grouped by 10 s. Record how many temperatures fell in each temperature interval, and draw the histogram. temperature interval 10 temp. < temp. < temp. < temp. < temp. < temp. < temp. < 80 how many days e. Make a histogram on your calculator of the temperatures grouped by 5 s. Draw the histogram. Also list the three temperature intervals that occurred the most often. temperature interval how many days