# Complete the problems below. Show some of your steps and explain the answer, too

Complete the problems below. Show some of your steps and explain the answer, too. If you use StatCrunch to compute a confidence interval, shot a screenshot of your output, or type out your input (so your work can be error-checked).
Question #1
A 95% confidence interval for a population proportion yielded the interval (.345, .455). (This is enough information to answer the following questions. Don’t over-think these questions!)
Compute the margin of error.
Compute the sample proportion.
Will a 90% confidence interval be wider or narrower? Explain.
Question #2
Many companies are interested in knowing the percentage of adults who buy clothing online. How many adults must be surveyed in order to be 95% confident that the sample percentage is in error by no more than three percentage points?
Use a recent result from the Census Bureau:  70% of adults buy clothing online.
Assume that we have no prior information suggesting a possible value of the proportion.
Question #3
A Pew Research Center poll of 1007 randomly selected adults showed that 42% of those survey feel the Internet is a bad influence on morality.
What is the value of n? pˆ?
Compute the margin of error E that corresponds to a 95% confidence level.
Compute the 95% confidence interval estimate of the population proportion p.
Based on the results, can we safely conclude that more than half of adults feel the Internet is a bad influence on morality?
Assuming that you are a newspaper reporter, write a brief statement that accurately describes the results and includes all of the relevant information.

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