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#1. What is the correct interpretation of the following 95% confidence interval

ID: 3367645 • Letter: #

Question

#1.

What is the correct interpretation of the following 95% confidence interval for mean # of cruffins (hybrid croissant + muffin) sold at a bakery? 95% CI: (130,180)

The average number of cruffins is between 130 and 180, 95% of the time.

We are 95% confident that the average number of cruffins sold at the bakery is between 130 and 180.

We are 95% confident that the average number of cruffins sold at the bakery is less than 130 and greater than 180.

We are 100% confused about what a cruffin is

#2  

A one-sample t-test that is two-tailed...

can be performed with either a p-value or confidence interval.

tests if the mean is different from, greater than, or less than a number.

uses a t and not a Z.

All of these

#3  

An independent-samples t-test showed that there was a significant difference in mean # of donut holes eaten between group A and B (p-value was less than 0.05). The average # of donut holes eaten was 20 in group A and 30 in group B. The average difference (30-20=10) can be thought of as the practical significance.

a. True

b. False

A.

The average number of cruffins is between 130 and 180, 95% of the time.

B.

We are 95% confident that the average number of cruffins sold at the bakery is between 130 and 180.

C.

We are 95% confident that the average number of cruffins sold at the bakery is less than 130 and greater than 180.

D.

We are 100% confused about what a cruffin is

Explanation / Answer

1) Option - B is correct.

2) Option - D is correct.

3) False