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Two-Way Tables

SECONDARY 1 MATH

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Two Way Table

a way to display frequencies or relative frequencies for two categorical variables

one category is represented in rows, the other category will be in columns

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Characteristic 1

Characteristic 2

Opposite of

Characteristic 1

Opposite of

Characteristic 2

Total

Total

Frequency, how often this

combination occurred

Sum of the row

Sum of the column

Grand Total of

all combinations

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Joint Frequencies

Marginal Frequencies

the number of times a combination of two conditions occur

entries that make up the “body” of the table

the number of times one specific condition occurs

entries that are in the “Total” of a row or column

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Survey the class to fill in the table according to which university they cheer for if BYU played Utah in a sporting match.

What percentage of the boys cheer for BYU?

What percentage of the girls cheer for Utah?

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Survey the class to fill in the table according to which university they cheer for if BYU played Utah in a sporting match.

What percentage of the people that cheer for BYU are girls?

What percentage of the class are BYU fans?

What percentage of the Utah fans are boys?

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Survey the class to fill in the table according to which university they cheer for if BYU played Utah in a sporting match.

Shade in the marginal frequencies, leave the joint frequencies white

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What observation can you

make about the boys?

a large majority of boys wanted soccer as the activity

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What observation can you

make about the girls?

a large majority of girls wanted a dance as the activity

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What observation can you

make about Dance?

Of the students that wanted a dance, only a small portion were boys

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What observation can you

make about Soccer?

More students preferred to hold a soccer game than a dance

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What percent of students

that wanted a soccer game

are boys?

 

74.07%

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What percent of students

wanting a dance are girls?

 

88.46%

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Ronnie is in charge of determining the upcoming after school activity.

To determine the type of activity, Rashid asked several students whether they prefer to have a dance or play a game of soccer. As Ronnie collected preferences, he organized the data in the following two-way frequency table:

What percent of total students

surveyed want a dance ?

 

49.06%

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A survey was done by the librarian and there were 45 total students who like to read books. Of those students, 12 of them like non-fiction and the rest like fiction. Four 7th Graders like non-fiction, and twenty 8th Graders like fiction.

45

12

4

20

33

8

28

13

17

What percentage of 8th graders like fiction?

 

71.43%

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A survey was done by the librarian and there were 45 total students who like to read books. Of those students, 12 of them like non-fiction and the rest like fiction. Four 7th Graders like non-fiction, and twenty 8th Graders like fiction.

45

12

4

20

33

8

28

13

17

What percentage of people that like nonfiction are in 7th grade?

 

33.33%

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A survey was done by the librarian and there were 45 total students who like to read books. Of those students, 12 of them like non-fiction and the rest like fiction. Four 7th Graders like non-fiction, and twenty 8th Graders like fiction.

45

12

4

20

33

8

28

13

17

What percentage of all the people like fiction?

 

73.33%

Shade in the marginal frequencies,

leave the joint frequencies white

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Divide the class according to whether their birthdays are in the first half of the year or last half, and whether they have brown eyes.

Jan-June

July-Dec

Brown Eyes

Not Brown Eyes

What percentage of the class has a birthday from January to June?

What percentage of the brown eyed students have later birth months?

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Divide the class according to whether their birthdays are in the first half of the year or last half, and whether they have brown eyes.

Jan-June

July-Dec

Brown Eyes

Not Brown Eyes

Shade the marginal frequencies, leave the joint frequencies white

What percentage of all students were born from July to December and do not have brown eyes?

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The Venn diagram compares 15 roller coasters at an amusement park as to whether or not they are made of steel and whether or not they have loops.

Made of Steel

Not Steel

Total

Has Loops

No Loops

Total

2

4

6

10

8

15

3

3

5

7

What percent of total roller coasters are steel?

 

53.33%

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The Venn diagram compares 15 roller coasters at an amusement park as to whether or not they are made of steel and whether or not they have loops.

Made of Steel

Not Steel

Total

Has Loops

No Loops

Total

2

4

6

10

8

15

3

3

5

7

What percent of roller coasters that have loops are not steel?

 

40%

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The Venn diagram compares 15 roller coasters at an amusement park as to whether or not they are made of steel and whether or not they have loops.

Made of Steel

Not Steel

Total

Has Loops

No Loops

Total

2

4

6

10

8

15

3

3

5

7

What percent of roller coasters that are steel also have loops?

 

75%

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The Venn diagram compares 15 roller coasters at an amusement park as to whether or not they are made of steel and whether or not they have loops.

Made of Steel

Not Steel

Total

Has Loops

No Loops

Total

2

4

6

10

8

15

3

3

5

7

What percent of roller coasters are neither made of steel nor have loops?

 

20%

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