Answer:
The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
For this problem, we have that:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
Answer:
Step-by-step explanation:
In each case, draw the right triangle which produces the inverse trig value. That is, label the two sides as needed, and calculate the third side.
It should be clear that


sin(2α) = 2 sinα cosα
So,

See what you can do with the others.
d)
First choice is an improper fraction because you can't have 22 ninths.
And the second two are just normal fractions, not wholes.
The first choice would be the right answer IF instead of writing it like that, it was written like this ( 2 4/9 )
Your answer is d).
Not sure what we need to do for this question, as it appears that you have already completed it, but looking over your answer, the graphed relationship looks correct! And it would take 3 cups of flour to make 90 cookies, as per the table.