8. a seventh - grade english language arts teacher wants to order books for all the seventh - grade classes…

8. a seventh - grade english language arts teacher wants to order books for all the seventh - grade classes. he wants to determine the favorite type of book among the seventh - grade students. which sample would be the most appropriate for this survey?\na. 7 girls in each of his classes\nb. every fifth student in the seventh grade\nc. 1 out of 7 students in his middle school\nd. all of the boys in one of his seventh - grade classes\n\n9. amber determined that the expression $\frac{-\frac{1}{2}}{-\frac{41}{15}}$ is equivalent to. which statement describes the process amber could have used?\na. she divided $-\frac{1}{2}$ by $- 15$ and then divided the result by 41.\nb. she multiplied $-\frac{1}{2}$ by $- 15$ and then divided the result by 41.\nc. she divided $-\frac{1}{2}$ by $- 15$ and then multiplied the result by 41.\nd. she multiplied $-\frac{1}{2}$ by $- 15$ and then multiplied the result by 41.

8. a seventh - grade english language arts teacher wants to order books for all the seventh - grade classes. he wants to determine the favorite type of book among the seventh - grade students. which sample would be the most appropriate for this survey?\na. 7 girls in each of his classes\nb. every fifth student in the seventh grade\nc. 1 out of 7 students in his middle school\nd. all of the boys in one of his seventh - grade classes\n\n9. amber determined that the expression $\frac{-\frac{1}{2}}{-\frac{41}{15}}$ is equivalent to. which statement describes the process amber could have used?\na. she divided $-\frac{1}{2}$ by $- 15$ and then divided the result by 41.\nb. she multiplied $-\frac{1}{2}$ by $- 15$ and then divided the result by 41.\nc. she divided $-\frac{1}{2}$ by $- 15$ and then multiplied the result by 41.\nd. she multiplied $-\frac{1}{2}$ by $- 15$ and then multiplied the result by 41.

Answer

8.

Brief Explanations:

A good sample should be representative of the entire seventh - grade student population. Option A only includes girls, option C includes students from the whole middle - school not just seventh grade, and option D only includes boys from one class. Option B, every fifth student in the seventh grade, is a form of systematic random sampling and is more likely to be representative of all seventh - grade students.

Answer:

B. every fifth student in the seventh grade

9.

Explanation:

Step1: Recall the rule of dividing by a fraction

Dividing by a fraction $\frac{a}{b}$ is equivalent to multiplying by its reciprocal $\frac{b}{a}$. The expression $\frac{-\frac{1}{2}}{\frac{-41}{15}}$ can be rewritten as $-\frac{1}{2}\times\frac{-15}{41}$. This means we first multiply $-\frac{1}{2}$ by $- 15$ and then divide the result by $41$.

Answer:

B. She multiplied $-\frac{1}{2}$ by $-15$ and then divided the result by $41$.