8.SP.4  Twoway Tables  Understand that patterns of association can also be seen in bivariate categorical data by displaying frequencies and relative frequencies in a twoway table. Construct and interpret a twoway table summarizing data on two categorical variables collected from the same subjects. Use relative frequencies calculated for rows or columns to describe possible association between the two variables. For example, collect data from students in your class on whether or not they have a curfew on school nights and whether or not they have assigned chores at home. Is there evidence that those who have a curfew also tend to have chores?

how to read a twoway table
A twoway table is a way to display data when you have two different variables (bivariate) and the values of those variables fit into different categories (categorical data). If you watch the slides below and to the left, you can start to get a sense of how the data is put into the categories. If you were to watch the video on the right, you will get a more complete explanation of how the process works and how the values are determined.

Below are some questions from the video to the left. Take some time to think about the answers to these questions, and then advance the slides to the right to see if your answer is correct.
There are 5 questions, and slide to the right to see the answer to each question. 
Finding the Values of a twoway table
When you are given information that can be constructed into a twoway table, you need to use addition and subtraction and logic in order to determine what values go where. Most of the time, you are using can use process of elimination to determine what value to compute next.
Isn't this a lot like a Sudoku???

Below are some questions from the video to the left. Take some time to think about the answers to these questions, and then advance the slides to the right to see if your answer is correct.
There are 3 questions to answer, and each answer is shown on 2 slides. 
twoway tables and Venn Diagrams
A twoway table is a way to display data when you have two different variables (bivariate) and the values of those variables fit into different categories (categorical data). If you watch the slides below and to the left, you can start to get a sense of how the data is put into the categories. If you were to watch the video on the right, you will get a more complete explanation of how the process works and how the values are determined.

Below are some questions from the video to the left. Take some time to think about the answers to these questions, and then advance the slides to the right to see if your answer is correct.
There are 3 questions to answer, and each answer is shown on 2 slides. 
Here is a section from a Glencoe book that I found online that may offer up some good chance to practice some problems.
