Identifying Representative Random and Biased Samples

Starla polled the 2 customers who had been going to a particular barbershop the longest.  Is this sample of the customers likely to be representative?

• yes

• no

Emma selected 5 essays from each student in her class.  Each student wrote the same number of essays.  Is this sample of the essays written by the class likely to be representative?

• yes

• no

Josie threw a handful of identically shaped buttons into the air, then collected the 27 buttons that landed in a target on the floor.  Is this a random sample of the buttons?

• yes

• no

Without looking, Christine took 2 flash cards out of her box of flash cards.  Is this a random sample of the flash cards?

• yes

• no

A town has 35,000 registered voters. A random sample of 500 voters finds that 125 are in favor of a new dog park. How many voters are likely to vote for the dog park?

• 8,750

• 2,625

• 125

• 2,500

A manager of a local store samples the receipts of every fifth person who goes through the line.  Out of 50 people, 4 had an item that was priced incorrectly.  If 600 people go through his store each day, how many people would you expect to have an incorrect price?

• 30

• 25

• 48

• 50

_________ 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

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

• Biased

• Unbiased

• Representative

• Numerical

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.

Choose the true statement(s) about the census and sample shown.

• The sample could be considered too small.

• The sample is biased because is does not include everyone.

• The sample is representative of the population's sub-groups.