Question

Karen wants to learn what sport is the favorite of students in the 7th and 8th grades at her school. She asks 15 of the 30 seventh graders in her math class to name their favorite sport. The results are summarized in the table below.

The table shows the percentage of students who like football is 26%, basketball is 30%, baseball is 35%, and soccer is 9%.

Which statements are true? Choose all that are correct.

A.
Karen's sample is representative of the population of all 7th and 8th graders at her school.

B.
Students in Karen's math class may not represent all 7th graders at her school very well.

C.
Karen can conclude that baseball is the favorite sport of 7th and 8th graders at her school.

D.
Karen can conclude that football is less popular than basketball among students in her math class.

E.
Karen should include 8th graders from her school in her sample.

Answer 1

Correct choices: B and E.

- A is false — she sampled only some students from one class and no 8th graders, so the sample isn't representative of all 7th and 8th graders.
- B is true — students in her math class could differ from other 7th graders, so they may not represent all 7th graders well.
- C is false — she didn't sample 8th graders and only asked half the students in one class, so she can't conclude the favorite for all 7th and 8th graders.
- D is false — she surveyed only 15 of the 30 students in her class, so she cannot confidently conclude the preference for the whole class.
- E is true — to learn about 7th and 8th graders together, she should include 8th graders in her sample.