Definitions
General Questions?
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Formulas
100
Mu

What is population mean?

100

If n = 13, what do we have to assume the shape of the population is if we want our sample to be appropriate for a one-sample t-interval? 

What is bell-shaped/normal? 

100

At a 93% confidence, what is zstar? Round to the second decimal place. 

What is 1.81?

100

If the margin of error and xbar is known, how can we find the lower bound and upper bound of the confidence interval?

What is (xbar - ME, xbar + ME)?

200

Within 4 units of 10, what would be the lower bound and the upper bound?

What is 6 and 14? 

200

If n is fixed and we want to make the margin of error smaller, what should we change? 

What is lower C%?

200

22 companies were sampled on how much money they made last week. With a sample average of $316 and a standard deviation of $89, what is the upper bound of a 95% confidence interval for the population mean? Round to the nearest whole number. 

What is about $355?

200

What is the ME formula using the z critical value?

What is ME = z-star * (sigma/sqrt(n))
300

What sample statistics is the best point estimate of mu? 

What is xbar/sample mean?

300

For this lesson, what are two distances that are equal to each other? 

What is the distance between the LB and xbar & xbar and UB?

300

If I have a confidence interval (238, 462), what is the margin of error? 

What is 112? 
300

What is the ME formula using the t critical value?

What is ME = t-star * (s/sqrt(n))?

400

What is the critical value in terms of the t-distribution? 

What is t-starn-1

400
How would we calculate the standard error of xbar? 

What is s/sqrt(n)?

400

If we want to be 90% confidence our estimate is within 5 inches of the population mean, how many people's heights should we measure given we had a sample of 14 people with a mean of 71 inches and a standard deviation of 10 inches in height? 

What is 11 people?

400

How would we calculate the minimum sample size required to achieve a specific C% within a specific ME? 

What is n = ((z-star*sigma)/ME)2
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