Trips to the Movies. Algebra II - Chapter 12 Review. Multiple Choice Identify the choice that best completes the statement or answers the question.

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1 Frequency Frequency Frequency Frequency Algebra II - Chapter 12 eview Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Suppose you spin two spinners. Each has equally likely outcomes, the numbers 1 through. Which graph shows the probability distribution for the sum of the two spinners? a. c b Sum d Sum Sum Sum 2. A set of data has one and only one mode. a. always b. sometimes c. never 3. The median of a set of data is equal to the third quartile. a. always b. sometimes c. never Short Answer 4. For two weeks, Mark recorded the color of the traffic light at the intersection of Main Street and North Avenue as his school bus approached the intersection. The results were: red, red, red, red, red, red, green, red, red, yellow. Make a frequency table for the data.. Use the frequency table. Find the probability that a person goes to the movies at least 8 times a month. ound to the nearest thousandth. Trips to the Movies Number of Movies Number of Moviegoers More than 7 movies per month movies per month movies per month 26

2 Less than 2 movies per month 226 Total The dartboard has 8 sections of equal area. The letters represent the colors red (), yellow (Y), blue (B), and green (G). Use a table to show the probability distribution for a dart that hits the board at a random location. Y G G G Y Y B 7. Suppose you roll two number cubes. Graph the probability distribution for the sample space {sum of numbers < 6, sum of numbers > 6, sum of numbers = 6}. 8. The table shows the results of a survey of students in two math classes. Find P(more than 1 hour of TV 6th period class). ound to the nearest thousandth. Did You Watch More Than One Hour of TV Last Night? Yes No 3rd period class th period class The table shows the results of a survey of college students. Find the probability that a student is taking a humanities class, given the student is male. ound to the nearest thousandth. First Class of the Day for College Students Male Female Humanities Science 0 80 Other The probability that a city bus is ready for service when needed is 84%. The probability that a city bus is ready for service and has a working radio is 67%. Find the probability that a bus chosen at random has a working radio given that it is ready for service. ound to the nearest tenth of a percent. Find the mean, median, and mode of the data set. ound to the nearest tenth , 13, 9, 9, 7, 1, 11, 10, 13, 1, 13 Make a box-and-whisker plot of the data.

3 12. average daily temperatures in Tucson, Arizona, in December: 67, 7, 2, 1, 64, 8, 67, 8,, 9, 66, 0, 7, 62, 8, 0, 8, 0, 60, 63 Find the values of the 30th and 90th percentiles of the data , 9, 7,, 11, 7, 17, 20, 19, 2, 17, 12,, 1, 13, 12, 11, 1, 16, 20 Find the outlier in the set of data , 4.6, 6.7, 0.4, 6.2, 4.8, 3.7, 3.1 Find the range and interquartile range of the data. ound to the nearest tenth , 4, 38, 8, 40, 3, 10,, 23, 36 Find the mean and standard deviation of the of data. ound to the nearest tenth , 16, 18, 14, 9, 20, Another measure of variation is variance, which equals. Find the variance and standard deviation of the data set. ound to the nearest tenth. 7, 8, 4, 10, 6, Susan keeps track of the number of tickets sold for each play presented at The Community Theater. Within how many standard deviations of the mean do all the values fall? 137, 134, 91, 61, 10, 1, 110, 148, 90, 169, 67, A set of data has mean 66 and standard deviation 7. Find the z-score of the value In a sample of 138 teenagers, 38 have never been to a live concert. Find the sample proportion for those who have never been to a live concert. 21. Find the margin of error for the sample proportion, given a sample size of n = ound to the nearest percent. 22. Find the sample size that produces the margin of error. 23. A survey of 480 high school students found that 37% had a pet. Find the margin of error. ound to the nearest percent. Use the margin of error to find an interval that is likely to contain the true population proportion. 24. The bar graph shows the rents paid per month for apartments in an urban neighborhood. The curve shows that the rents are normally distributed. Estimate the percent of apartment residents who pay from $600 to $749 per month.

4 4 % of espondents <$600 $ $ $ >$749 ent 2. A set of data with a mean of 6 and a standard deviation of 3.3 is normally distributed. Find the values that are 2 standard deviations from the mean. 26. The numbers of cookies in a shipment of bags are normally distributed, with a mean of 64 and a standard deviation of 4. What percent of bags of cookies will contain between 60 and 68 cookies? 27. A grocery store will only accept yellow onions that are at least 3 in. in diameter. A grower has a crop of onions with diameters that are normally distributed, with a mean diameter of 3.2 in. and a standard deviation of 0.2 in. What percent of the onions will be accepted by the grocery store? 28. Participants in a study of a new medication received either medication A or a placebo. Make a tree diagram of the results of the study. Then find P(placebo and improvement). Of all those who participated in the study, 80% received medication A. Of those who received medication A, 76% reported an improvement. Of those who received the placebo, 62% reported no improvement. 29. A restaurant chain s owners are trying to decide if they want to open up a franchise in your town. To help them decide, they want to find out how often people in your town go out to eat. A researcher interviews people leaving a local restaurant. Is there a bias in this sampling method? Explain. 30. Label each section of the spinner so the spinner has the probability distribution: P(red) = 0., P(green) = 0.12, P(blue) = 0.2, P(yellow) = 0.12.

5 31. In a sample of 230 teenagers, 202 would like to have smaller class sizes at their school. Find the sample proportion, the margin of error, and the interval likely to contain the true population proportion. If necessary, round your answers to the nearest percent. 32. Sketch a normal curve with a mean of 0 and a standard deviation of 2. Label the x-axis at one, two, and three standard deviations from the mean.

6 Algebra II - Chapter 12 eview Answer Section MULTIPLE CHOICE 1. C 2. B 3. B SHOT ANSWE % 11. mean = 9.3, median = 10, mode = th percentile = 9; 90th percentile =

7 1. range = 47; interquartile range = mean = 16.1; standard deviation = variance = 4.6; standard deviation = % margin of error = ; interval, 32% to 42% % and % % P(placebo and improvement) = 29. Yes. Explanations may vary. Sample: The survey would likely miss people who eat out infrequently or not at all. People leaving a restaurant are likely to eat out more often than the general population. 30. Answers may vary. Sample: G Y B B 31. sample proportion = 88% margin of error = % interval: 81% to 9%

8 32. Mean 1 deviation +1 deviation 2 deviations +2 deviations 3 deviations +3 deviations