Answer:
They can either decrease the confidence level or increase the sample size, that is, survey more students.
Step-by-step explanation:
The width of a confidence interval is given by:
In which z is the critical value correponding to the confidence level(higher confidence level, higher z is), 
is the standard deviation of the population and n is the size of the sample.
The students realize that this interval contains a large margin of error. What can they do to make a narrower interval?
Looking at the formula for M, they can either decrease the confidence level or increase the sample size, that is, survey more students.
Answer:
x ≤ -259/9
Step-by-step explanation:
Change into a number equation 9(x + 26) ≤ -25
Starting from what I know (the difference between ribbons), I decided to go from the bottom and work my way up. I then noticed a pattern (each sum was three more of the previous one), and decided to keep my pattern of the three numbers but not have to do any major mental work and instead add three to the previous sum until I got to 38.
<u>Answer:</u>
<u>Null hypothesis: Policy B remains more effective than policy A.</u>
<u>Alternate hypothesis: Policy A is more effective than policy B.</u>
<u>Step-by-step explanation:</u>
Remember, a hypothesis is a usually tentative (temporary until tested) assumption about two variables– independent and the dependent variable.
We have two types of hypothesis errors:
1. A type I error occurs when the null hypothesis (H0) is wrongly rejected.
That is, rejecting the assumption that policy B remains more effective than policy A when it is <em>actually true.</em>
2. A type II error occurs when the null hypothesis H0, is not rejected when it is actually false. That is, accepting the assumption that policy B remains more effective than policy A when it is <em>actually false.</em>
