MAS 291 EXAM 2 QUESTIONS AND 100% CORRECT ANSWERS!!

MAS 291 EXAM 2 QUESTIONS AND 100%
CORRECT ANSWERS!!
b

A. Reject HO if the test statistic is greater than 1.96 or less than -1.96
B. Reject HO if the test statistic is greater than 1.645 or less than -1.645.
C. Reject HO if the test statistic is greater than 2.33 or less than -2.33
D. Reject Ho if the test statistic is greater than 2.575 or less than -2.575.
E. None of the other choices is correct

E

A CD has 12 tracks on it and these are to be played in random order. Suppose that you have time
to listen to only 5 tracks before you go out. What is the probability that the 5 played will be the
first 5 in order on the box?


A. 1/3991680
B. 5/12
C. 1/792
D. None of the other choices is correct
E. 1/95040

C

Suppose that P(A|B) = 0.6, P(A) = 0.5 and P(B) = 0.1. Find the value of P(B|A).


A. 0.20
B. 0.30
C. 0.12
D. None of the other choices is correct
E. 0.06

B

,Let X be a uniform random variable over the interval [1, 9]. What is the probability that the
random variable X has a value less than 6?


A. None of the other choices is correct
B. 0.625
C. 0.400
D. 0.875
E. 0.500

C

A quality-control engineer inspects a random sample of 3 batteries from each lot of 24 car
batteries that is ready to be shipped. If such a lot contains 6 batteries with slight defects, what is
the probability that the inspector's sample will contain only one of the batteries with defects?


A. 0.1832
B. 0.5464
C. 0.4536
D. None of the other choices is correct
E. 0.8168

A

A. (I)
B. (II)
C. (III)
D. None of the other choices is true

A

Suppose a sample of n = 15 items is drawn from a population of manufactured products and the
weight, X, of each item is recorded. Prior experience has shown that the weight has a probability
distribution with mean = 6 ounces and standard deviation = 2.5 ounces. Which of the following
is true about the sampling distribution of the sample mean if a sample of size 15 is selected?

,A. The mean of the sampling distribution is 6 ounces.
B. All of the others are correct.
C. The shape of the sample distribution is approximately normal.
D. The standard deviation of the sampling distribution is 2.5 ounces.

B

A. 0.4
B. 0.3
C. 0.5
D. 0.2
E. None of the other choices is correct

E

A. None of the other choices is correct
B. 0.0294
C. 0.0559
D. 0.0668
E. 0.0359

C

Choose the correct phrase to fill in the blank:
The _______ for a particular class is equal to the class frequency divided by the total number of
observations.


A. class percentage
B. bar graph
C. class relative frequency
D. stem-and-leaf display
E. None of the other choices is correct

B

, Consider the following sample data:
25 11 6 4 2 17 9 6
For these data the median is_______________


A. 10
B. 7.5
C. None of the other choices is correct
D. 3.5

D

It is desired to estimate the average total compensation of CEOs in the Service industry. Data
were randomly collected from 35 CEOs and the 94% confidence interval was calculated to be
(3451260, 7536180). Which of the following interpretations is correct?


A. 94% of the sampled total compensation values fell between 3451260 and 7536180


B. We are 94% confident that the mean of the sampled CEOs falls in the interval 3451260 to
7536180


C. In the population of Service industry CEOs, 94% of them will have total compensations that
fall in the interval 3451260 to 7536180


D. We are 94% confident that the average total compensation of all CEOs in the Service industry
falls in the interval 3451260 to 7536180

D

The number of calls received by a car towing service averages 21.6 per day (per 24-hour period).
After finding the mean number of calls per hour, find the probability that in a randomly selected
hour the number of calls is 4.


A. 0.01389
B. None of the other choices is correct