Answer:
17.5%
Step-by-step explanation:
First of all, see this situation as a cumulative binomial distribution. You have isolated trials with a probability of success. This makes it binomial. The wording of the question "what is the probability of at least half..." makes this cumulative.
There are a few ways to calculate this, and I'm not quite sure which way you're familiar with. I'll show the cumbersome way and use wolfram to make the calculation.
First, I'll calculate the probability for 15 success, given 30 trials.
30c15*0.4^15*0.6^15
Since the question asks for the probability of at least 15 success, I'll have to make a calculation for the probability of 16 successes, then 17, and so on. Then I'll have to add all the probabilities together. So, I'll use wolfram for that (see attached)
A. 72÷9÷2 = 8÷2 = 4
b. (18 ÷ 6) ÷ 3 = 3 ÷ 3 = 1
c. 45 ÷ 5 ÷ 3 = 9 ÷ 3 = 3
d. 144 ÷ (12 ÷ 2) = 144 ÷6 = 24
Answer:
your answer should be $16.50 :)
Step-by-step explanation:
Answer:
Correct option: B
Step-by-step explanation:
The professor can perform a One-mean <em>t</em>-test to determine whether the average score of the students in his class is more than the average score of all the students attending university.
A <em>t</em>-test will be used instead of the <em>z</em>-test because the population standard deviation is not provided instead it is estimated by the sample standard deviation.
The hypothesis for this test can be defined as follows:
<em>H₀</em>: The average score of the students in his class is not more then the entire university, i.e. <em>μ ≤ 35</em>.
<em>Hₐ</em>: The average score of the students in his class is more then the entire university, i.e. <em>μ > 35</em>.
Given:
The test statistic is:
Thus, the correct option is (B).
