Statistics and Probability Review Part 1

Joey plans to survey his classmates about which presidential candidate for whom they will vote. Which group(s) of classmates should Joey poll for valid results? Select ALL that apply.

• A) randomly selected classmates of both genders

• B) randomly selected classmates in the Environmental Club

• C) randomly selected females in his class

• D) randomly selected classmates from each homeroom

Mr. Blaine wants to survey a random sample of students at his middle school about the amount of homework assigned each night. Which surveying method is the best option?

• A) surveying all of the school’s eighth grade students

• B) surveying all of the students who stay for the math bowl practice

• C) surveying every fourth student as they arrive to school in the morning

• D) surveying all of the students who play a musical instrument at the school

Is the survey sample a valid representation of the entire school, and why?

• No. Adam does not survey members of the school band.

• No. Adam does not survey students from other grades.

• Yes. Adam samples a large group and has a good representation of the school.

• Yes. Adam surveys all seventh graders.

If Ramiro’s school has a total enrollment of 908 students, about how many students in the school could be expected to prefer pepperoni pizza based on the survey Ramiro conducted?

• 190 students

• 320 students

• 450 students

• 590 students

A teacher wants to find out what incentive seventh-grade students prefer. Which group is the most representative of the population of interest?

• all the students in the middle school

• all the seventh-grade students in the robotics club

• every sixth student to walk into the middle school one morning

• six randomly selected students from each seventh-grade class

A writer for a woman's magazine surveys women leaving a clothing store to determine which brand of clothing women like the most. Which statement best explains that the results of this survey may not be valid?

• The survey should have been conducted online.

• The group surveyed consisted only of women.

• The survey was conducted by a writer from only one magazine.

• The group surveyed consisted only of women who shopped at a particular store.

The Yum-Yum Candy Factory wants to know which type of candy is most popular with people aged 30 – 50. Which would be the best group to sample?

• A group of middle school students who buy candy at least once a week.

• A group of parents with middle school aged children.

• A group of adults who have at least five grandchildren.

• A team of professional basketball players.

Which survey question is most likely to result in an unbiased sample?

• Which do you like better, delicious apples or boring oranges?

• Do you prefer apples, like I do, or oranges?

• Don't you prefer apples to oranges?

• Which do you prefer, apples or oranges?

Which inference can be drawn based on the results?

• Less students prefer pepperoni pizza than cheese and sausage pizza combined.

• Less students prefer cheese than sausage.

• No students like sausage.

• More students prefer pepperoni than cheese.

Two elementary schools each conducted a survey of 100 fifth grade students asking about their favorite ice cream flavors. The results of the surveys are listed in the chart. Survey Location | Chocolate | Vanilla | Strawberry | Total School #1 | 37 | 47 | 16 | 100 School #2 | 44 | 25 | 31 | 100 Which is a valid inference about the data?

• Chocolate is a more popular flavor at School #1 than it is at School #2.

• More students prefer chocolate than both vanilla and strawberry combined at School #1.

• Approximately twice as many students prefer strawberry at School #1 than at School #2.

• If both schools are combined, the most popular flavor is chocolate.