1. 12-2 Conditional Probability Obj: To be able to find conditional probabilities and use formulas and tree diagrams

2. What is Conditional Probability?

3. Examples Using Tree Diagrams

4. 12-3 Analyzing Data Obj: To be able to calculate measures of central tendency and draw box-and-whisker plots.

5. Measures of Central Tendency Mean – average Median – middle number Mode – number that occurs the most (“bimodal” – data set that has two modes)

6. Example 1 Ms. Christ’s math quiz grades in Algebra 2 – 93, 95, 89, 90, 80, 102, 89, 100, 91 Find: a)Mean b)Median c)Mode = 92.1 = 91 = 89

7. Box and Whisker Plots Min Max Q1 Q2 Q3 Number Line Q1 = Median of lower part Q2 = Median of entire data set Q3 = Median of upper part

8. Example 2 28 47 35 42.5 25 30 35 40 45 50 Q1 = 28, 29, 31, 34 Q2 = Middle of 34 & 36 Q3 = 36, 40, 45, 47 Make a box-and-whisker plot: 34, 36, 47, 45, 28, 31, 29, 40 = 28, 29, 31, 34, 36, 40, 45, 47 30

9. Percentiles If you scored in the top 5 th percentile on a standardized test, that means that 95% of the test takers scored less than you. 14, 12, 10, 13, 7, 16, 11, 13, 20, 15 Find the value at the 30 th percentile. There are 10 values in the data set. 7, 10, 11, 12, 13, 13, 14, 15, 16, 20 10 ∙.30 = 3 Find the number that is greater than 3 values. 12 is at the 30 th percentile.

10. Outliers Numbers that mess up your data. 100, 99, 105, 2, 103, 98, 106 If these were the grades of your math tests, getting a 2% would totally mess up your average.

11. Homework P. 652 #1-11 odd