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QUESTION 1
Every sixth person in the school cafeteria was asked to name where he or she would like to go for the school’s spring outing. Fifteen chose an amusement park, 10 chose a baseball game, 10 chose a water park, and 6 choose an art museum. What is the probability that a student prefers to go to an amusement park?
Suppose there are 408 students at Julia’s school. Predict how many students prefer going to an amusement park.
ANSWER TO QUESTION 1
Every sixth person in the school cafeteria was asked to name where he or she would like to go for the school’s spring outing. Fifteen chose an amusement park, 10 chose a baseball game, 10 chose a water park, and 6 choose an art museum. What is the probability that a student prefers to go to an amusement park?
Suppose there are 408 students at Julia’s school. Predict how many students prefer going to an amusement park.
About 150 students
QUESTION 2
According to one survey, 25% of high school students reported that they would not get summer jobs. Predict how many of the 948 students at Mohawk High School will not get a summer job.
ANSWER TO QUESTION 2
According to one survey, 25% of high school students reported that they would not get summer jobs. Predict how many of the 948 students at Mohawk High School will not get a summer job.
About 237 students
QUESTION 3
Every tenth student who walked into the cafeteria was surveyed to determine his or her favorite lunch. Out of 40 students, 19 students stated that they liked baked potato bar the best. The staff concluded that about 50% of the students like baked potatoes the best for lunch. Is the sample method valid? Justify your answer.
ANSWER TO QUESTION 3
Every tenth student who walked into the cafeteria was surveyed to determine his or her favorite lunch. Out of 40 students, 19 students stated that they liked baked potato bar the best. The staff concluded that about 50% of the students like baked potatoes the best for lunch. Is the sample method valid? Justify your answer.
The conclusion is valid. This is unbiased and a systematic random sample.
QUESTION 4
The library is trying to decide what types of books to sell at its book fair. It surveyed 40 students at random. The results are in the table. If 220 books are to be sold at the book fair, how many should be mysteries?
ANSWER TO QUESTION 4
The library is trying to decide what types of books to sell at its book fair. It surveyed 40 students at random. The results are in the table. If 220 books are to be sold at the book fair, how many should be mysteries?
66 books
QUESTION 5
Janet surveyed the athletes on the girls’ field hockey team to determine which sports teenagers like best. Of these, 85% said that they liked field hockey the best. Janet concluded that over three-fourths of teenagers like field hockey best. Is this sample method valid? Justify your answer.
ANSWER TO QUESTION 5
Janet surveyed the athletes on the girls’ field hockey team to determine which sports teenagers like best. Of these, 85% said that they liked field hockey the best. Janet concluded that over three-fourths of teenagers like field hockey best. Is this sample method valid? Justify your answer.
This is not a valid conclusion. This is biased survey since Janet only surveyed
one team.
QUESTION 5
Michael and Melissa both claim to be earning a C average – 70% to 70% - in their Latin class. One student is wrong. Which one? Explain how he or she is using a misleading statistic.
ANSWER TO QUESTION 5
Michael and Melissa both claim to be earning a C average – 70% to 70% - in their Latin class. One student is wrong. Which one? Explain how he or she is using a misleading statistic.
Michael is wrong. Although his median is a C, his
average grade is below 70%.
QUESTION 6
The line graph show the sales for the Crumbly Cookie Bakery. Which graph makes it appear that the sales declined only slightly? Is this graph valid?
ANSWER TO QUESTION 6
The line graph show the sales for the Crumbly Cookie Bakery. Which graph makes it appear that the sales declined only slightly? Is this graph valid?
Graph A; this is not valid since it goes from 0-
600, then increases by 200.
QUESTION 7
In your own words, what does “sample” mean?
ANSWER TO QUESTION 7
In your own words, what does “sample” mean?
A sample is a smaller group of the population.
QUESTION 8
Fill in the blanks:
_______ _______ and _________ _________ are two types of unbiased samples.
ANSWER TO QUESTION 8
Fill in the blanks:
Simple random and systematic random are two types of unbiased samples.
QUESTION 9
A travel agent surveyed her customers to determine their favorite vacations locations. Use the table to find the probability of choosing of a beach vacation. Write your answer as a percent.
Location Customers
Amusement park
2
Beach 11Campground 8National Park 4
ANSWER TO QUESTION 9
A travel agent surveyed her customers to determine their favorite vacations locations. Use the table to find the probability of choosing of a beach vacation. Write your answer as a percent.
44%
Location Customers
Amusement park
2
Beach 11Campground 8National Park 4
QUESTION 10
The number of points Emerson scored in 5 basketball games is 10, 8, 9, 8, and 30. Why might it be misleading for Emerson to say that he averages 13 points per game?
ANSWER TO QUESTION 10
The number of points Emerson scored in 5 basketball games is 10, 8, 9, 8, and 30. Why might it be misleading for Emerson to say that he averages 13 points per game?
The mean is 13, but he only scored over 10 points once in five games.
QUESTION 11
An owner of a restaurant wants to conduct a survey about possible menu changes. Which of the following sampling methods would produce a valid sample?
a. Survey every fifth person entering the mall
b. Survey five of his friends
c. Survey every fifth person eating at the owner’s restaurant
d. Survey every fifth person registered at the restaurant’s Web site
ANSWER TO QUESTION 11
An owner of a restaurant wants to conduct a survey about possible menu changes. Which of the following sampling methods would produce a valid sample?
a. Survey every fifth person entering the mall
b. Survey five of his friends
c. Survey every fifth person eating at the owner’s restaurant
d. Survey every fifth person registered at the restaurant’s Web site
QUESTION 12
Which of the following statements are true?
a. The IQR of the 7th grade is lower than the IQR of the 8th grade
b. The median for 8th grade is 25.
c. The 8th grade range is more than the 7th grade range.
ANSWER TO QUESTION 12
Which of the following statements are true?
a. The IQR of the 7th grade is lower than the IQR of the 8th grade
b. The median for 8th grade is 25.
c. The 8th grade range is more than the 7th grade range.
QUESTION 13
Which of the following statement is true about the dot plots?
a.Smoothies Galore has a greater median than Sunshine Smoothies.
b.Smoothies Galore has a median less than Sunshine Smoothies.
c.The median of both companies are exactly the same.
d.Since the graphs are not symmetric, you should use the mean absolute deviation to compare the two populations.
ANSWER TO QUESTION 13
Which of the following statement is true about the dot plots?
a.Smoothies Galore has a greater median than Sunshine Smoothies.
b.Smoothies Galore has a median less than Sunshine Smoothies.
c.The median of both companies are exactly the same.
d.Since the graphs are not symmetric, you should use the mean absolute deviation to compare the two populations.
QUESTION 15
The double box plot shows the number of weekly participants at two community center summer camps. Compare the centers.
ANSWER TO QUESTION 15
The double box plot shows the number of weekly participants at two community center summer camps. Compare the centers.
Both populations
have the same median
of 60.
QUESTION 16
Match the appropriate display for each situation.
a.The resale value of a person’s car over time.
b.The percent of people that drink 0, 1, 2, 3, or more than 3 glasses of water a day.
c.The number of different colored shoes at a shoe store.
1.Bar graph
2.Line graph
3.Histogram
4.Circle graph
ANSWER TO QUESTION 16
Match the appropriate display for each situation.
a.The resale value of a person’s car over time.
b.The percent of people that drink 0, 1, 2, 3, or more than 3 glasses of water a day.
c.The number of different colored shoes at a shoe store.
1.Bar graph
2.Line graph
3.Histogram
4.Circle graph
VOCABULARY
Know these vocabulary words:Unbiased sample
Population
Survey
Biased survey
Voluntary response sample
Statistics
Double box plot
Simple random
sample
Sample
