Types of Samples

Zach is trying to decide which of the three golf courses is the best. He randomly surveyed people at a sports store and recorded the results. What kind of sample is this?

A store manager sends an E-mail survey to customers who have registered at the store's Website. What kind of sample does the survey use?

Maci surveyed all the members of her softball team about their favorite sport. What kind of sample does this survey use?

Is this a biased or unbiased sample? You want to know the average height of seventh graders so you ask 20 students who you see walking in front of the cafeteria at the beginning of the day.

Is this a biased or unbiased sample? You want to know the favorite exploratory of 8th graders. You randomly select 4 students from each 8th grade advisement to survey.

Is this an unbiased or biased sample? You want to know if you think this class activity is boring. So you post a question on teams asking students to comment with their answer.

Ms. Hernandez uses a random sample to figure out how many of her students in her class bring an umbrella on days it is predicted to rain. She finds out that 4 out of 7 students bring an umbrella. How many students should she predict bring an umbrella out of 35 students?

Mrs. Smith uses a random sample to ask her all of her math classes, how many of them have their iPad charger at home or needs to pay the fine. She finds that 18 out of 25 have their charger. How many should she predict have their charger out of 75 students?