8 - 1 Two-Way Frequency Tables: Categorical Data and Frequencies
8 - 1 Two-Way Frequency Tables: Categorical Data and Frequencies
                                                                                                                                                           Resource
                                                                                                                                                            Locker
                                                         Explore            Categorical Data and Frequencies
                                                 Data that can be expressed with numerical measurements are quantitative data. In this lesson you will examine
                                                 qualitative data, or categorical data, which cannot be expressed using numbers. Data describing animal type,
                                                 model of car, or favorite song are examples of categorical data.
                                                        A frequency table shows how often each item occurs in a set of categorical data. Use the
                                                         categorical data listed on the left to complete the frequency table.
Reflect
1. How did you determine the numbers for each category in the frequency column?
2. What must be true about the sum of the frequencies in a frequency table?
     A high school’s administration asked 100 randomly selected students in the 9th and 10th
      grades about what fruit they like best. Complete the table.
                                                         Preferred Fruit
           Grade             Apple               Orange               Banana                     Total
             9th                19                  12                    23
            10th                22                   9                    15
           Total
       Row totals:                       Column totals:                   Grand total:
       9th: 19 + 12 + 23 = 54            Apple: 19 + 22 = 41              Sum of row totals: 54 + 46 = 100
       10th: 22 + 9 + 15 = 46            Orange: 12 + 9 = 21              Sum of column totals: 41 + 21 + 38 = 100
                                                         Preferred Fruit
           Grade             Apple               Orange               Banana                     Total
             9th                19                  12                    23                      54
            10th                22                   9                    15                      46
           Total                41                  21                    38                     100
B     Jenna asked some randomly selected students whether they preferred dogs, cats, or other
      pets. She also recorded the gender of each student. The results are shown in the two-way
      frequency table below. Each entry is the frequency of students who prefer a certain pet and
      are a certain gender. For instance, 8 girls prefer dogs as pets. Complete the table.
Girl 8 7 1
Boy 10 5 9
Total
3. Look at the totals for each row. Was Jenna’s survey evenly distributed among boys and girls? Explain.
4. Look at the totals for each column. Which pet is preferred by the most students? Justify your answer.
Your Turn
                                                 5.     Antonio surveyed 60 of his classmates about their participation in school activities and whether they have a
                                                        part-time job. The results are shown in the two-way frequency table below. Complete the table.
                                                                                                                Activities
                                                                Job         Clubs Only         Sports Only            Both           Neither            Total
                                                                Yes             12                 13                  16                4
                                                                 No              3                  5                  5                 2
                                                                Total
6. Jen surveyed 100 students about whether they like baseball or basketball. Complete the table.
                                                                                                        Like Basketball
                                                            Like Baseball                Yes                    No                     Total
                                                                   Yes                   61                      13
                                                                   No                    16                      10
                                                                  Total
                                                        Suppose you are given the circled information in the table and instructed to complete
                                                         the table.
                                                       Lunch Beverage
           Gender             Juice                 Milk                Water            Total
Girl 10 17
Boy 15 24 21 60
Total
So, the total number of girls is . The number of girls who do not choose milk is + = .
Reflect
Your Turn
8.     100 students were asked what fruit they chose at lunch. The two-way frequency table shows some of the
       results of the survey. Complete the table.
                                                           Lunch Fruit
           Gender            Apple                 Pear              Banana              Total
               Girl                                  17                  11                49
9.     200 high school teachers were asked whether they prefer to use the chalkboard or projector in class.
       The two-way frequency table shows some of the results of the survey. Complete the table.
                                                 11. A 3 categories-by-3 categories two-way frequency table has a row with 2 numbers, and no row or column
                                                     totals. Can you fill the row?
12. Essential Question Check-In How can you summarize categorical data for 2 categories?
                                                                                                                soup
                                                       corn soup soup corn peas
                                                       peas corn soup peas corn
                                                                                                                peas
                                                       peas corn peas corn soup
                                                       corn peas soup corn corn
                                                 3.   James surveyed some of his classmates about what vegetable they like best.
                                                      Complete the table.
                                                                                            Preferred Vegetable
                                                         Grade          Carrots          Green Beans            Celery             Total
                                                             9th           30                  15                  24
10th 32 9 20
Total
                                               Like Tennis
           Like Soccer             Yes               No               Total
              Yes                  37                20
No 16 15
Total
5.   After a school field trip, Ben surveyed some students about which animals they liked
     from the zoo. Complete the table.
12th 4 17 15
Total
6.   Jill asked some randomly selected students whether they preferred blue, green, or
     other colors. She also recorded the gender of each student. The results are shown in
     the two-way frequency table below. Complete the table.
                                               Preferred Color
           Gender           Green             Blue            Other             Total
             Girl             15                3               10
Boy 3 16 6
7.   Kevin surveyed some students about whether they preferred soccer, baseball, or
     another sport. He also recorded their gender. Complete the table.
                                               Preferred Sport
           Gender           Soccer          Baseball          Other             Total
             Girl             33                7               10
Boy 15 27 7
Total
                                                                                                                   Like Backgammon
                                                                                  Like Chess            Yes                  No             Total
                                                                                       Yes              10                   61
No 5 3
Total
                                                                          9.   Hugo surveyed some 9th and 10th graders in regard to whether they preferred math,
                                                                               English, or another subject. The results of the survey are in the following table.
                                                                               Complete the table.
                                                                                                                         Preferred Subject
                                                                                      Grade            Math             English            Other           Total
                                                                                       9th              40                   35              20
10th 41 32 17
Total
                                                                          10. Luis surveyed some middle school and high school students
                                                                              about the type of music they prefer. Complete the table.
© Houghton Mifflin Harcourt Publishing Company • Image Credits: ©Dragon
                                                                                                                    Preferred Music
                                                                                     School Level       Country        Pop        Other    Total
                                                                                  Middle School               18        13         23
High School 7 32 15
Total
                                                                          11. Natalie surveyed some teenagers and adults on whether they prefer standard cars,
                                                                              vans, or convertibles. Her results are in the following table. Complete the table.
Images/Shutterstock
Teenagers 11 7 24
Total
                                              Preferred Fruit
             Age           Apple           Orange            Banana              Total
            Adults           22               12                  10
Teenagers 24 9 9
Total
200 students were asked to name their favorite science class. The results are shown
in the two-way frequency table. Use the table for the following questions.
Boy 45 32
             Total
13. How many boys were surveyed? Explain how you found your answer.
14. Complete the table. How many more girls than boys chose biology as their favorite
    science class? Explain how you found your answer.
Boy 35 8 5
           Total
15. Complete the table. Do the surveyed students own more laptops or more
    electronic tablets?
16. Which group had more people answer the survey, boys or students who own an
    electronic tablet only? Explain.
                                                                                               Preferred Flavor
                                                        Gender            Vanilla               Mint             Strawberry          Total
                                                          Girl                                   15                   18                45
                                                          Boy                17                  25
                                                         Total                                                                       100
                                                 18. Teresa surveyed 100 students about whether they like pop music or country music. Out
                                                     of the 100 students surveyed, 42 like only pop, 34 like only country, 15 like both pop and
                                                     country, and 9 do not like either pop or country. Complete the two-way frequency table.
                                                                                                        Like Pop
                                                        Like Country                  Yes                  No                    Total
                                                             Yes
                                                             No
                                                            Total
                                                 19. Forty students in a class at an international high school were surveyed about which
                                                     non-English language they can speak. Complete the table.
                                                                                                Foreign Language
                                                            Gender           Chinese          Spanish             French            Total
                                                              Girl                7                8
                                                              Boy                                  6                  7              18
                                                             Total
                                                 Luis surveyed 100 students about whether they like soccer. The number of girls and
                                                 the number of boys completing the survey are equal.
                                                                                                       Likes Soccer
                                                            Gender                    Yes                  No                    Total
                                                              Girl                                          20
                                                              Boy                                           35
                                                             Total                                                                100
                                                 21. Twice as many girls like soccer as the number that like tennis. The same number of
                                                     students like soccer as like tennis. Construct a table containing the tennis data.
Likes Tennis
                                                    Text Messages
           Email                     Yes                    No                       Total
             Yes                      72                                              90
No 45
Total
23. Circle the letter of each data set that is categorical. Select all that apply.
		A. 75°, 79°, 77°, 85°
C. male, female
24. Explain the Error Find the mistake in completing the two-way frequency table for
    a survey involving 50 students. Then complete the table correctly.
Boy 42 9 7 58
Correct table:
Boy 9 7
Total
                                                 25. Justify Reasoning Charles surveyed 100 boys about their favorite color. Of the
                                                     100 boys surveyed, 44 preferred blue, 25 preferred green, and 31 preferred red.
                                                     a. Explain why it is not possible to make a two-way frequency table from the given
                                                        data.
                                                     b. Suppose Charles also surveyed some girls. Of the girls surveyed, 30 preferred blue
                                                        and 43 preferred green. Can Charles make a two-way frequency table now? Can
                                                        he complete it?
                                                 26. Persevere in Problem Solving Shown are two different tables about a survey
                                                     involving students. Each survey had a few questions about musical preferences.
                                                     All students answered all questions. Complete the tables. What type of music do
                                                     the students prefer?
Boy 22
Total 100
Boy 15
Total
                                           Favorite Sport
           Gender         Football      Baseball      Basketball      Soccer        Total
           Female                                          36            12
Male 38 19
Total 64 36
     b. Which sport is the most popular among the students? Which is the least popular?
        Explain.
     c.    Which sport is most popular among the females? Which sport is most popular
           among the males? Explain.