Two-Way Frequency Table Analysis

Hello! Today we are going to complete a two-way frequency table and use it to identify correct statements about a survey on students' water consumption. All numbers provided are in thousands.

First, we look at the row for ninth-grade students. We know the total is forty-five thousand. The sum of the columns for zero to two glasses and three to four glasses is ten plus thirteen, which is twenty-three. So, the missing value for five or more glasses is forty-five minus twenty-three.

Now we can look at the column for five or more glasses. The total is thirty-nine. We just found that twenty-two ninth-graders fall here. Subtracting twenty-two from thirty-nine tells us there are seventeen tenth-grade students in this category.

Next, let's find the total number of tenth-grade students by subtracting the ninth-grade total from the grand total of one hundred seven. One hundred seven minus forty-five gives us sixty-two.

With sixty-two as the total for tenth-graders, we can find those drinking zero to two glasses. We subtract the other tenth-grade categories, twenty-six and seventeen, from sixty-two. This leaves us nineteen.

Finally, we fill in the column totals. For zero to two glasses, ten plus nineteen is twenty-nine. For three to four glasses, thirteen plus twenty-six is thirty-nine.

Here is our completed table. Let's use these values to check the statements in Part B.