1. Which stat plot has a higher standard deviation?

2. Given the standard deviations, which data has the most variability? Data A: 23.5 Data B: 19.2 Data C: 26.4 3. Population or Sample Standard Deviation? - You want to poll students in our class about how many texts are sent per day

4. Population or Sample Standard Deviation? The State Government wants to determine 9th graders GPA in Georgia. 5. Which data is the least consistent given the following standard deviations? Data A: 2.5 Data B: 1.6 Data C: 0.4 6. Given the following standard deviations, which data set varies the least from its mean? Data A: 27 Data B: 34 Data C: 29

7. Population or Sample Deviation? Analyzing your test grades 8. Which data set is the most consistent given the following standard deviations? Data A: 7.9 Data B: 8.5 Data C: 7.23 9. Population or Sample Deviation? Analyzing SAT scores in the nation

10. Population or Sample Standard Deviation? How many hours do people in our class watch TV? 11. Which data has the least variability given the standard deviations? Data A: 12.1 Data B: 12.01 Data C: 12.11 12. Just by looking at the data, which set would have a higher standard deviation? Why? Data A: 90, 81, 72, 100, 68, 92, 90 Data B: 1, 1, 2, 2, 1, 1, 2

14. We want to compare the class averages between 2nd and 3rd period. 13. Just by looking at the data, which set would have a higher standard deviation? Why? Data A: 5, 15, 7, 20, 2, 18, 3, 11 Data B: 80, 81, 80, 79, 81, 80 14. We want to compare the class averages between 2nd and 3rd period. Find the mean and standard deviation.

Find the mean and standard deviation. 15. Cobb County is analyzing sophomore averages in Math 2 across the county. They choose 5 classes from 2 random schools. Find the mean and standard deviation. 16. You polled 10 groups of 15 seniors to determine how many universities Georgia seniors are applying to. Listed below are the averages for each group. Find the mean and standard deviation

Which questions are biased? 17. What is your favorite type of music? 18. You like the show American Idol, don’t you? 19. To find out the average sophomore class GPA, you ask students in Honors English. 20. You ask the first 20 students who arrive at Hillgrove: How do you get to school in the mornings?

Which sample is least representative of the population? 21. The population data for our poll: Which sample is least representative of the population? Why? 22. The population data for our poll: Which sample is least representative of the population? Why? A 5 7 9 8 B 4 11 C

23. Which stat plot has a higher mean?

24. Which stat plot has a higher mean?

25. Which stat plot has greater variability?

26. Which stat plot has a smaller standard deviation?

Without a calculator: The following two sets of data have the same mean, but which one has a larger standard deviation? Data 1: 72, 67, 65, 73, 75, 68, 70 Data 2: 65, 60, 80, 75, 70, 90, 50

28. Without a calculator: The class average on a test is 72. I add 5 points to every test. Which changed, the mean or the standard deviation?

Daily Check Population or Sample Standard Deviation? a. Mrs Smith wants to average the number of hours she watched TV last week. b. You want to average the sophomore class GPA at Hillgrove. Calculate the mean and sample standard deviation by hand. 12, 9, 11, 8, 9