Question

Nayara wants to know the percentage of each grade level of students at her school who drive to school. She has 4 grade levels in her school.

Answer 1

Nayara wants to know the percentage of each grade level of students at her school who drive to school. She has 4 grade levels in her school.

Explanation:

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Answer 2

Randomly select 12 students from each grade level and ask whether they drive to school.

Explanation:

1/3: Both methods are random, but only one method gives Nayara an equal chance of surveying every student within a grade level.

2 / 3: If Nayara selects students who drive to school, she has no chance of selecting students in the grade level who do not drive to school.

3 / 3 The valid method: Randomly select 12 students from each grade level and ask whether they drive to school.