Unit 3: Chapter 8.2 Means

Question 1

The mean of a t distribution is

Answer 1

0

Question 2

The median of a t distribution is

Answer 2

0

Question 3

The standard deviation of a t distribution is

Answer 3

1>

Question 4

The variance of a t distribution is

Answer 4

1>

Question 5

The degrees of freedom in a t distribution is

Answer 5

n-1

Question 6

A t distribution is a normal distribution

Answer 6

true

Question 7

Another name for the standard normal distribution is the t distribution.

Answer 7

false

Question 8

The t distribution has an infinite possible number of degrees of freedom, one for each possible sample size.

Answer 8

true

Question 9

For a confidence level of 98% with a sample size of 21, find the critical t value.

Answer 9

2.528

Question 10

A student was asked to find a 99% confidence interval for widget width using data from a random sample of size n = 19. Which of the following is a correct interpretation of the interval 12.7 < μ < 32.7?

Answer 10

With 99% confidence, the mean width of all widgets is between 12.7 and 32.7.

Question 11

construct a 80 percent confidence interval with n=15, X bar=47, and s =15

Answer 11

critical t value= 1.345
df=14
E=5.209
(41.8, 52.2)

Question 12

Beyond representative sampling, what assumptions are needed to satisfy the requirements of a one-sample means interval?

Answer 12

The sample size should be at least 30 or the population have a normal distribution