Remember that the cells in the last row and column of a two-way frequency table represent the total number of respondents belonging to a particular category.
See solution.
Practice makes perfect
Let's take a look at the example two-way frequency table where which not all of the cells are filled in.
Favorite Type of Chocolate
Age Group
Dark
Milk
White
Total
Children
?
19
6
25
Teenagers
13
?
?
?
Adults
23
?
19
78
Total
?
81
?
150
We can fill in the rest of the table in a variety of orders. However, we should start with a row or a column in which we do not know the value of only 1 cell. In our table, we can start with the first row.
Favorite Type of Chocolate
Age Group
Dark
Milk
White
Total
Children
?
19
6
25
Teenagers
13
?
?
?
Adults
23
?
19
78
Total
?
81
?
150
In the last column we have the number of children that took part in our survey. This means that the number of children that like dark chocolate is the total number of children minus the number of children that like milk and white chocolate.
25- 19- 6=0
We can see that 0 children chose dark as their favorite type of chocolate.
Types of Chocolate
Age Group
Dark
Milk
White
Total
Children
0
19
6
25
Teenagers
13
?
?
?
Adults
23
?
19
78
Total
?
81
?
150
We can fill the whole table by using the same logic. Whenever there is only one empty cell in a row or a column, we can fill it in by using the fact that the cells in the last row and the last column represent the total numbers of respondents that chose the particular category.
Therefore, we should decide where to start filling a two-way frequency table based on the number of empty cells in a row or a column.
