What is exactly in the middle of the given confidence interval? Circle ALL the correct answers:
What is the margin of error of the given confidence interval?
What could be done to reduce the margin of error? List two ways to achieve this goal.
True or False?
If they had taken 100 samples of 50 randomly selected hybrid cars and had calculated a 95%
confidence interval from each sample, probably about 95 of these confidence intervals would not
contain the population parameter, and about 5% would contain it.
A magazine article titled
Are You Ready for an Interview?
claims that 50% of all senior executives
say that the most common job interview mistake is to have little or no knowledge of the company.
To check this claim, Accountemps (a company specialized in temporary professional accounting and
finance positions) conducted a survey of 155 randomly selected senior executives, and found that 66
of them said just that: the most common job interview mistake is to have little or no knowledge of
the company. Based on these survey results, can you conclude that the magazine’s article published
a false claim? (That is not 50%?)
Specify the null and alternative hypotheses for this test, using the correct symbols and numbers.
Check the conditions for a hypothesis test.
Determine the value of the test statistic, and the p-value.