BUAL 2650 Exam 1 Questions and Answers

BUAL 2650 Exam 1 Questions and Answers
Question 1
What are the 2 kinds of random variables?

Correct Answer
discrete (countable) and continuous (decimals)



Question 2
P (z< 2)
Correct Answer
0.9772



Question 3
What are some other names for a continuous probability distribution?
Correct Answer
probability curve and probability density function (pdf)



Question 4
What is the most common type of continuous probability distribution?
Correct Answer
normal distribution



Question 5
What is H0?

Correct Answer
null hypothesis (describes an exciting theory)




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,Question 6
P (-1 < z< 2)
Correct Answer
0.8185



Question 7
What is a statical inference?
Correct Answer
Point Estimation



Question 8
What is n?
Correct Answer
sample size



Question 9
Mxbar = ?
Correct Answer
M



Question 10
What is xbar?
Correct Answer
the sample mean



Question 11
How do you calculate a z-score?
Correct Answer
(value-mean)/standard deviation




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, Question 12
What percent of the area under the normal curve is within 3 standard deviation to the
left and right?
Correct Answer
99.73



Question 13
Suppose we will randomly select a sample of 64 measurements from a population
having a mean equal to 20 and a standard deviation of 4. Find the mean and standard
deviation of the sample.
Correct Answer
xbar=20, std. dev. =0.5



Question 14
What does the shape of any individual normal curve depend on?
Correct Answer
its specific mean and standard deviation (also median and mode)



Question 15
What is the confidence coefficient?
Correct Answer
the confidence level or (1-a)



Question 16
Do the tails of a normal curve ever touch the horizontal axis?
Correct Answer
no




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