TWO-WAY FREQUENCY TABLES

WARM UP  Find the outlier of the following set of data and determine how it will skew our data:  Test Scores:  100, 100, 99, 95, 97, 95, 99, 97, 94, 40

OBJECTIVE  The student will be able to create a two-way frequency table and calculate relative frequency.

EXPLORATION  Who has been out of the country?  Who has been out of the state?  Who said no to both?

WITH A PARTNER  Create a two way frequency table of the following data:  Students who play sports: 45  Students who are in the play: 40  Students who do both: 15  Students who participate in neither: 10

TWO-WAY FREQUENCY TABLES  Show data that pertain to two different categories.  The data from one sample group is shown how it relates to two different categories.  Very Similar to Venn Diagrams

HOW TO CONSTRUCT A TWO- WAY FREQUENCY TABLE Play a SportDo not Play a Sport Total In the Play Not in the Play Total

WITH A PARTNER  Construct a Two-way Frequency Table with the following data:  After taking a survey of the 8 th grade Algebra classes(50 students), Mr. Holocker found that 40 students have cell phones and of those 40 students 35 of them have an MP3 player. He found that 5 students did have a MP3 player and not a cell phone and he found 5 students who had neither. Create a two-way frequency table of the data.

WITH A PARTNER…  Find the Relative Frequency of the following table: Play a SportDo not Play a Sport Total In the Play Not in the Play Total453580

CALCULATING RELATIVE FREQUENCY  Relative Frequency is the ratio of the subgroups total compared to the entire sample population.  Take the total in the cell and divide it by the total sample population.  *Rounded values—you can round when necessary. Frequency by Row Play a SportDo not Play a Sport Total In the Play15/40 =.37525/40 = Not in the Play30/40 =.7510/40 = Total45/80 =. 56*35/80 =.44*1.00

CONTINUED  You can calculate relative frequency by columns as well: Frequency by Column Play a SportDo not Play a Sport Total In the Play15/45 =.3325/35 =.7140/80 =.5 Not in the Play30/45 =.6710/35 =.2940/80 =.5 Total1.00

WITH A PARTNER  Calculate the Relative frequency by row and column of the following: Have Been to Canada Have Not Been to Canada Total Have Been to Mexico 639 Have Not Been to Mexico Total111425

ON YOUR OWN  Create a two way frequency table and calculate the relative frequency, by row and column, of the following:  As each person entered the theater, Charlie Brown counted how many of the 105 people had popcorn and how many had a drink. He found that out of 84 people that had popcorn, only 10 did not have a drink. Six people walked in without popcorn or a drink.

EXIT TICKET AND HOMEWORK  Exit Ticket:  How do you calculate relative frequency?  Homework:  Worksheet.