A simple random sample of voters is taken from the voters in a large state. Using the methods of our course, researchers construct an approximate 99% confidence interval for the percent of the state’s voters who will vote for Candidate A. The interval goes from 37.3% to 48.7%.

In the sample, the percent of voters who will vote for Candidate A is equal to ____________%.

Question

A simple random sample of voters is taken from the voters in a large state. Using the methods of our course, researchers construct an approximate 99% confidence interval for the percent of the state’s voters who will vote for Candidate A. The interval goes from 37.3% to 48.7%.

In the sample, the percent of voters who will vote for Candidate A is equal to ____________%.

amistre64 · Answer

well, since an interval is centered around the sample mean ....  what is the midpoint between 37.3 and 48.7?

amistre64 · Answer

even if they are using "approximation" ; that is still 3 standard deviations centered about the sample mean

anonymous · Answer

The middle point is (37.3+48.7)/2 =43

anonymous · Answer

For A, I would find the center of 
 37.3% to 48.7%.

i.e.   (37.3 + 48.7)/2 = 43.0

the interval from 43 to 48.7 =  5.7  represents 2.58 σ  so
 5.7/2.58 = 2.21 % per  σ

anonymous · Answer

is correct the statement?

amistre64 · Answer

$$p\pm E$$
$$37.3~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~48.7\~~~|<------p------>|\~~~~~~~~~~~~~-E~~~~~~~~~~~~~~~~~~~~+E$$
the sample percentage is the midpoint between the extremes

amistre64 · Answer

add the ends and divide in half

$$\frac{37.3+48.7}{2}=\frac{86.0}{2}=43$$

amistre64 · Answer

43% of the sample choose A

amistre64 · Answer

finding the sample size would be fun :)

anonymous · Answer

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