1. Unit 3 – Lesson 2 10/20

3. Use your notes from yesterday to find the standard deviation of the following set of data: At least FIVE of your (or a friend’s) homework scores (highlighted in blue on the cabinet)

5.  How many boys were surveyed?  How many girls were surveyed?  Explain how you determined the number of girls and boys that were surveyed.

6.  How many girls can not roll their tongues?  How many males can roll their tongues?  How many boys and girls can roll their tongues?

7.  Entries in the "Total" row and "Total" column are called marginal frequencies, or the marginal distribution.  Entries in the body of the table are called joint frequencies.

8.  We can also display relative frequencies in two-way tables. The relative frequencies in the body of the table are called conditional frequencies or the conditional distribution.  These are PERCENTAGES  Number in the category divided by the total

9. Showing Relative Frequencies

10. Let’s try it again!

11. Has a dogDoes not have a dog Total Has a cat Does not have a cat Total

12. VCRNo VCRTotal Computer No Computer Total

13. 16 or 16.00 80 x.20 00 160 16 00

14.  Find 25 percent of 1,245.  Find approximately 83% of 672.

15.  Create your own 2-way table by surveying the class!  Pick two of these categories: gender, if they play an instrument, grade level, whether they are a morning person or night person, and if they are a Carolina Panthers fan.  Create a table to display your data.  Make sure to use the conditional frequency which is a percentage!