Quiz Submissions - Quiz 7
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The report of a sample survey of 1014 adults says, "with 95%
confidence, between 9% and 15% of all Americans expect to spend
more on gifts this year than last year."
What does the phrase "95% confidence" mean?
Question options:
mericans will spend between 9% and 15% more than what they spent last year.
used to get the interval 9% to 15%, when used over and over again, produces intervals which include the true population proport
f all Americans will spend 95% of what they spent last year.
% chance that the percent who expect to spend more is between 9% and 15%.
What is the critical value of t for a 90% confidence interval with df =
14? (Assume a 2-tailed test)
Question options:
2.62449
2.14479
1.345030
1.761310
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points
, What is the critical value for a 95% confidence interval based on a
sample size of 20? (Population standard deviation is unknown).
(Assume a 2-tailed test)
Question options:
2.09302
2.08596
1.729133
1.724718
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points
A survey of 30 random shoppers found a 95% confidence interval
that shoppers will spend between $24.50 and $28.30.
A second survey surveyed 25 random shoppers.
Question options:
nterval will be narrower because the sample size is smaller and this creates less uncertainty.
nterval will be narrower because it is likely that there are less outliers.
nterval will be wider because the sample size is smaller and this creates more uncertainty.
nterval will be wider because it is likely that there are more outliers.
A survey of 503 citizens found that 370 of them favor a new bill
introduced by the city.
We want to find a 95% confidence interval for the true proportion of
the population who favor the bill.
What is the lower limit of the interval? (Round to 3 decimal digits)
Your quiz has been submitted successfully.
points
The report of a sample survey of 1014 adults says, "with 95%
confidence, between 9% and 15% of all Americans expect to spend
more on gifts this year than last year."
What does the phrase "95% confidence" mean?
Question options:
mericans will spend between 9% and 15% more than what they spent last year.
used to get the interval 9% to 15%, when used over and over again, produces intervals which include the true population proport
f all Americans will spend 95% of what they spent last year.
% chance that the percent who expect to spend more is between 9% and 15%.
What is the critical value of t for a 90% confidence interval with df =
14? (Assume a 2-tailed test)
Question options:
2.62449
2.14479
1.345030
1.761310
View Feedback
points
, What is the critical value for a 95% confidence interval based on a
sample size of 20? (Population standard deviation is unknown).
(Assume a 2-tailed test)
Question options:
2.09302
2.08596
1.729133
1.724718
View Feedback
points
A survey of 30 random shoppers found a 95% confidence interval
that shoppers will spend between $24.50 and $28.30.
A second survey surveyed 25 random shoppers.
Question options:
nterval will be narrower because the sample size is smaller and this creates less uncertainty.
nterval will be narrower because it is likely that there are less outliers.
nterval will be wider because the sample size is smaller and this creates more uncertainty.
nterval will be wider because it is likely that there are more outliers.
A survey of 503 citizens found that 370 of them favor a new bill
introduced by the city.
We want to find a 95% confidence interval for the true proportion of
the population who favor the bill.
What is the lower limit of the interval? (Round to 3 decimal digits)
