All else being equal, the higher the confidence level

	the wider the confidence interval
	the narrower the confidence interval

is the formula to calculate the

	sample mean
	sample proportion
	margin of error

What is the percentage of a t-distribution that is less than the mean?

	1
	50
	.5
	cannot say without knowing the t-score

All else being equal, the larger the sample size

	the wider the confidence interval
	the narrower the confidence interval

What should be the value of z used in a 93% confidence interval?

	2.70
	1.40
	1.81
	1.89

A 95% confidence interval for the mean number of televisions per American household is (1.15, 4.20). Of 100 intervals calculated the same way (95%), we expect 95 of them to capture the population mean.

	True
	False

How does the shape of a t-distribution with a small df compare with a normal distribution?

	The t-distribution has a smaller peak value and is higher in the tails.
	The t-distribution has a higher peak value and is lower in the tails.
	The t-distribution is very close to matching the normal distribution.