STATS Quiz 3.1-3.4

What is a requirement of a statistical question?

• one set answer

• a variety of answers

Choose the statistical question:

• How many sixth graders ate breakfast on Monday?

• How many sixth graders eat breakfast each school day?

A researcher stood at a school parking lot entrance to see if the color of a car is related to the driver not wearing a seatbelt.

• Observational Study

• Experiment

One group of subjects was given an herbal supplement and another group was given a placebo. After one year, the number of illnesses each group had was compared.

• Observational Study

• Experiment

1. A sample in which every person, object, or event has an equal chance of being selected.

• A. Random sample.
• B. Biased sample.

4. Carlos wants to know the favorite sport of people at his school so he asks his baseball team. Is his sample a biased or unbiased?

• A. Biased

• B. Unbiased

_______ is a part of a group being surveyed.

• Sample
• Population
• Random Sample
• Quartile

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.

How do we reduce variability?

• Increase randomness.

• Increase sample size.

• Decrease randomness.

• Decrease sample size.

A recent survey found that out of 400 random American adults, 89% pay their bills on time. The margin of error in this survey was 2%. What is the interval of values in which the truth is likely found?

• 89% - 91%

• 87% - 89%

• 87% - 91%

• 388 - 402