The answer is a because it is saying the corrext answer to the question
Answer: Mean = 52.8 mins
Step-by-step explanation:
We have lapses of 30 minutes, so we can write the average for each, this means that:
0 < t < 30 can be averaged to the middle of the range: 15 min.
Doing this, we have that:
7 students 15 min
27 students 45 min
12 students 75 min
4 students 105 min.
Now we can calculate the mean:
mean = (x1*n1 + x2*n2 + ...)/N
where x1 is the amount of time 1, and n1 is the number of students associated to that time and so on. N is the total number of students
Mean = (7*15min + 27*45min + 12*75min + 4*105min)/(7 + 27 + 12 + 4)
Mean = 52.8 mins
Answer:


⇻<u>Option B. x - 2</u> is the correct answer.
Answer:
C. If 75% of Americans still favor mandatory testing this year, then there is a 3% chance that poll results will show 72% or fewer with this opinion.
Step-by-step explanation:
Significance level or alpha level is the probability of rejecting the null hypothesis when null hypothesis is true. It is considered as a probability of making a wrong decision. It is a statistical test which determines probability of type I error. If the obtained probability is equal of less than critical probability value then reject the null hypothesis. In this question the sample of 1000 Americans is under test. It is the result of the poll that 75% still favor mandatory testing.
1. simplify 11/5
- 58/10 - 11/5 =0
2. Divide z by 11/5
- 58/10 - 5z/11 =0
3. simplify 29/5
29/5 - 5z/11 =0
4. calculating the least common multiple
4.1 find the least common multiple
the left denominator is: 5
the right deniminator is: 11
least common multiple:55
....
solution z=319/25 = 12.760