7.3 Practice 7th grade

You want to know which store shoppers at the mall visit the most. You ask each 10th person as they enter the mall which store they will visit. Biased or unbiased

• Biased: because it's at the mall

• Unbiased: they are asking every 10th person

You want to know which store shoppers visit the most. You enter the toy store and survey 20 customers. Biased or unbiased

• Biased: it's done at a store they are shopping at so most likely they like that store

• Unbiased: it's 20 customers

A hip-hop radio station wants to know what type of music is the most popular. They ask their listeners to call in and select their favorite type of music. Biased or unbiased

• Biased: they're tuning into a hip-hop station so they most likely like hip-hop

• Unbiased: it's done randomly

You want to know what the 7th grade students think of their science class. You poll 100 random 7th graders.

• Biased: it was only 100 people

• Unbiased: it was done randomly

You want to survey the students in your school about their exercise habits. At lunchtime you stand by the salad line. You survey every student who bought salads for lunch. Biased or unbiased.

• Biased: it was only people who eat salads which means they have healthier lifestyles

• Unbiased: it was done randomly

Your teacher is selecting students to help set up for a school dance. Only 5 students are needed to help. She puts everyone’s name in a hat and selects 5 names without looking. Biased or unbiased

• Biased: not everyone likes hats

• Unbiased: there's a fair chance for anyone to get picked

A cell phone company selects 500 customers from its database and then surveys those customers to find out if they like their phone service. Biased or unbiased.

• Biased: they are selecting their own customers, of course they like the service

• Unbiased: it's 500 customers

The owners of a local game store sends 150 random customers a survey. Biased or unbiased.

• Biased: it's only 150 surveys

• Unbiased: it was done randomly

You want to know how many students in our school have broken a bone. You survey the members of the football team. Biased or unbiased.

• Biased: they are more likely to break a bone playing a sport

• Unbiased: football players always answer honestly

The movie theater wants to know what genre of movies their customer enjoy. They survey all the people attending the children's matinee. Biased or unbiased.

• Biased: it was during a children's matinee

• Unbiased: they surveyed everyone