Answer:
95% confidence interval: (0.325 ,0.383)
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 231
Sample mean = 0.354 ppm
Sample standard deviation = 0.231 ppm
95% confidence interval:
Putting the values, we get,
We have that the total students there are 500. The 12-graders there are 200. Probability is defined as the ratio of positive outcomes of an event, over all the possible outcomes. Suppose we pick student randomly. Then, there are 200 positive outcomes (positive outcome: we pick a student in 12th grade) and there are totally 500 outcomes (we can pick 500 students in total from Riverside High School). This ratio gives:

. The requested probability is 0.40
Answer:
x= 425
Step-by-step explanation:
Answer:
Reduced form
Step-by-step explanation:
Hope this helps!