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.

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

Step-by-step 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.

step-by-step explanation:

we are given

since, we have to isolate x on anyone side

so, we can move all x terms on one side

subtract both sides by 2x

add both sides by 9

divide both sides by 4

we get