A financial analyst wanted to estimate the mean annual return on mutual funds. A random sample of 60 funds' returns shows an average rate of 12%. If the population standard deviation is assumed to be 4%, the 95% confidence interval estimate for the annual return on all mutual funds is
A. 0.037773 to 0.202227
B. 3.7773% to 20.2227%
C. 59.98786% to 61.01214%
D. 51.7773% to 68.2227%
E. 10.988% to 13.012%
Answer: E. 10.988% to 13.012%
Step-by-step explanation:
Given;
Mean x= 12%
Standard deviation r = 4%
Number of samples tested n = 60
Confidence interval is 95%
Z' = t(0.025)= 1.96
Confidence interval = x +/- Z'(r/√n)
= 12% +/- 1.96(4%/√60)
= 12% +/- 0.01214%
Confidence interval= (10.988% to 13.012%)
4 will be the correct answer to your question
<h2>
Answer with explanation:</h2>
Let p be the population proportion of parents who had children in grades K-12 were satisfied with the quality of education the students receive.
Given : Several years ago, 39% of parents who had children in grades K-12 were satisfied with the quality of education the students receive.
Set hypothesis to test :

Sample size : n= 1055
Sample proportion : 
Critical value for 95% confidence : 
Confidence interval : 

Since , Confidence interval does not contain 0.39.
It means we reject the null hypothesis.
We conclude that 95% confidence interval represents evidence that parents' attitudes toward the quality of education have changed.
Answer:
63
Step-by-step explanation:
Since a1=7 and the question is to find a9, you just have to multiply 7 and 9 which is 63
There are 6 different ways:
23,598
23,958
25,398
25,938
29,538
29,358