Download Unit 4 Statistics Study Guide

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Unit 4 Statistics Study Guide
1. Jerome wants to find out which is the favorite dessert for the students in his middle school. He
surveys five students in his homeroom and reports the results. Is his sample a random sample
that would be valid to determine the favorite dessert for the middle school? Why or why not?
2. Sandy wants to determine which ride is the favorite at Disney World. She surveys every 4 th
person that exits the park on a certain day. Is her survey a good sample to draw a valid
inference? Why or why not?
3. The soccer team is trying to determine what types of chips to sell in the concession stand.
Which of the following would be the best sample for their survey to draw a valid inference?
a. three randomly chosen students from each homeroom class
b. all band students
c. everyone at Burger King
d. all athletes in the school
4. Based on this chart, what inference can you draw about who will likely be the winner of the
student council race?
Candidate
Number of
Expected Votes
Anne Jones
16
Earl Ramirez 34
Jeremy Smith 20
5. What is the difference between the medians of New York and Seattle?
6. The five number summary for a set of data is shown:
Min: 4
Q1: 9
Q2: 23
Q3: 42
Max: 56
What is the interquartile range for this set of data?
The stem-and-leaf plots show test scores for two classes. Use these data displays to answer
questions 7 and 8.
7. Find the mean for Class A and the mean for Class B. Tell how much more or how much less
the mean for Class A is than the mean for class B.
8. Find the range of each class. Tell how much more or how much less the range for Class A is
than the range for class B.
9. Adrienne measured the heights of seven of her classmates. The heights were 48 inches, 52
inches, 50 inches, 58 inches, 54 inches, 56 inches, and 70 inches. What is the outlier in the
data set?
Use the information below to answer questions 10-14.
The lengths, in seconds, of four folk songs are 128, 165, 182, and 141.
The lengths, in seconds, of four pop songs are 90, 98, 102, and 94.
10. What is the mean length, in seconds, of the folk songs?
11. What is the mean absolute deviation, in seconds, of the folk songs?
12. What is the mean length, in seconds, of the pop songs?
13. What is the mean absolute deviation, in seconds, of the pop songs?
14. Compare the variability in seconds of the folk songs and pop songs. How many times more or
less is the variability of the folk songs than the pop songs.
15. The histogram below shows heights of students. Make at least two inferences
from the data.
16. The box plots show the times it takes for two different companies to make a repair service call.
Which company would you choose if you want your service call to take 46 minutes or less? Explain?
17. Rhonda surveys 90 high school students who are leaving a rock concert to determine the favorite
type of music among high school students. Explain why this sample may be biased.
Below is the data collected from two random samples of 100 students regarding each student’s
school lunch preference. Make at least TWO inferences based on the result.
Student
Sample
#1
#2
18.
19.
Chicken
sandwich
12
12
Cheese
Sticks
14
11
Nachos
Total
74
77
100
100
20. Harry’s test scores in science are: 85, 87, 82, 90, 80, 79, 88, 85 and 40. Identify the outlier in this
data set and explain how this outlier affects the mean.
21. Which measure of center (mean, median, or mode) is greatest for this set of data?
Using this box-and-whisker plot, answer questions 24-30:
Ray and Ken play 40 games of golf over a one-year period. Their scores are shown in the double
box-and-whisker plot below.
22. Which player had the least (minimum) score?
23. Which player had the greatest average (mean) score?
24. Which player’s data display shows a more predictable score?
25. Which player had the greatest (maximum) score?
Use the line plots below to answer questions 26-28.
A
B
26. Analyze the data above. Without actually computing the mean absolute deviation (MAD)
determine which data set, Sample A or Sample B, would have a greater MAD. Explain your
answer.
27. Compare the range for data sets A and B.
28. Data set A shows the lengths of pencils in a package bought at Wal-Mart. Data set B shows
the lengths of pencils bought at the Dollar Tree. Sam made a pencil box to store his pencils.
The pencil box was 5 inches long. Would more pencils from Wal-Mart or the Dollar Tree fit in
his box? Explain.