Answer: 3
Explanation:
Students that takes course one or both courses.
20 + 25 = 45
Students that take course. Not including both courses students.
45 - 8 = 37
Students that doesn’t take course.
40 - 37 = 3
The sample used in this problem is classified as cluster.
<h3>How are samples classified?</h3>
Samples may be classified as:
- Convenient: Drawn from a conveniently available pool.
- Random: All the options into a hat and drawn some of them.
- Systematic: Every kth element is taken.
- Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
- Stratified: Also divides the population into groups. Then, a equal proportion of each group is surveyed.
For this problem, a group of schools is selected, and then the new program is applied to all students in these school, meaning that all elements in the cluster are surveyed, so cluster sampling is used.
More can be learned about classification of samples at brainly.com/question/25122507
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Answer: the first one is exponential and the second one is function
4 because if u where to fold it