Populations and Samples in Probability

_______ is a part of a group being surveyed.

• Sample
• Population
• Random Sample
• Quartile

_________ is a sample in which each individual or object in the entire population has an equal chance of being selected.

• Sample
• Population
• Random Sample
• Quartile

_______ is the entire group of objects or individuals considered for a survey.

• Sample
• Population
• Random Sample
• Quartile

True or False: all samples lead to a good prediction about an entire population.

• True
• False

A school surveys all 7th grade boys to determine what to sell in the school store.  This sample is _________.

• Biased
• Unbiased
• Representative
• Peanut butter cups

A school survey asked 50 girls to identify their favorite items on the school cafeteria menu. This sample is ________________.

• Biased
• Unbiased
• Representative
• Numerical

A student wants to know which type of pizza the students at his high school prefer. Which option would give a unbiased, representative sample:

• Asking all the students in the hot lunch line.
• Asking 10 random students from each homeroom.
• Asking every other student who gets off a school bus.
• Asking all the 10th graders.

A city council member wanted to know how her constituents felt about a planned rezoning. She randomly selected 75 names from the city phone directory and conducted a phone survey.

• The population is everyone listed in the city phone directory; the sample is the 75 people selected.
• The population is residents of the city; the sample is the registered voters in the city.
• The population is registered voters in the city; the sample is everyone listed in the city phone directory.

A safety inspector conducts air quality tests on a randomly selected group of 7 classrooms at an elementary school.

• The population is all classrooms in the district; the sample is the 7 classrooms selected.
• The population is all classrooms in the elementary school; the sample is the 7 classrooms selected.
• The population is all elementary students in the school; the sample is the students in the 7 classrooms selected.

The choir director in a high school wants to know how the students in the school feel about singing. If the director selects 100 girls and 100 boys to complete a survey, which method will result in a biased sample?

• The students will be selected from the choir
• The students will be selected randomly throughout the school
• The students will be selected on Wednesday afternoon before the choir concert
• The choir director will select five students from each of the forty homerooms in the school