I would go with C because if you do A then its all new students and thats one view D is the same. C seems like the best choice.
Floor seats because for every balcony seat you get 20 floor seats.
hope this helps :P
Answer:
B. 71.43%
Step-by-step explanation:
The sensitivity is the probability that a test will indicate 'disease' among those with the disease, that is, the test has a positive results:
In this problem, we have that:
150 people with the disease tested positive and 60 tested negative. So the sensitivity is:
The correct answer is:
B. 71.43%
It may help you to consider the standard normal curve. If the mean here is 70%, then 0.5 of the area under this curve. In other words, half the students received a grade > 70%. That would be 100 students.
Note that 84 is 2 std dev above the mean.
Recall the Empirical Rule: 95% of scores lie within 2 std. dev of the mean.
Measuring from the mean, that would be 47.5% above the mean and 47.5% below the mean. The area to the right of the mean is 0.5. Subtract 0.475 from that to obtain the fraction of students who rec'd a grade greater than 2 std dev from the mean: It's 0.025.
Then the # of students who rec'd a grade greater than 84% would be
0.025(200 students) = 5 students.
