AnswersMathematics III AHypothesis Testing

Hypothesis Testing — Unit test Answers

14 verified answers1 views
1
Free Preview

A convenience sample differs from a voluntary sample in that

A
a convenience sample is structured based on accessibility to the researcher, and a voluntary sample is based on participant interest.
B
convenience samples survey each participant once, and voluntary samples survey each participant numerous times.
C
convenience sampling is a method of random sampling, and a voluntary sample is not.
D
convenience sampling is not a probability-based method, and voluntary sampling is.
2
Free Preview

The stem-and-leaf plot below shows the number of pages each student in a class read the previous evening.Which statement is true about the data set?

Question illustration
A
Its median is greater than its mode.
B
It has a range of 52 pages.
C
The value of the first quartile is 13.
D
The data is symmetric.
3

Emi computes the mean and variance for the population data set 87, 46, 90, 78, and 89. She finds the mean is 78. Her steps for finding the variance are shown below.What is the first error she made in computing the variance?

Question illustration
A
Emi failed to find the difference of 89 - 78 correctly.
B
Emi divided by N - 1 instead of N.
C
Emi evaluated (46 - 78)2 as -(32)2.
D
Emi forgot to take the square root of -135.6.
4

The mean test scores with standard deviations of four English classes are given below.ClassMeanStandard DeviationMrs. Jones891.9Mrs. Rijo821.4Mr. Phan733.4Mrs. Scott906.1Which statement is most likely to be true?

A
The scores of Mrs. Scott’s class are the closest to the class mean.
B
The scores of Mr. Phan’s class are the closest to the class mean.
C
The scores of Mrs. Jones’s class are the closest to the class mean.
D
The scores of Mrs. Rijo’s class are the closest to the class mean.
5

Two students have devised a dice game named “Sums” for their statistics class. The game consists of choosing to play odds or evens. Probabilities for “Sums”Roll23456789101112P(roll)Each person takes turns rolling two dice. If the sum is odd, the person playing odds gets points equal to the sum of the roll. If the sum is even, the person playing evens gets points equal to the sum of the roll. Note that the points earned is independent of who is rolling the dice.If Jessica is challenged to a game of Sums, which statement below is accurate in every aspect in guiding her to the correct choice of choosing to play odds or evens?

Question illustration
A
E(evens) will be more because there are more even numbers that result from rolling two dice. Therefore, Jessica should play evens.
B
E(odds) will be more because the probability for each odd number being rolled is greater. Therefore, Jessica should play odds.
C
E(evens) will be more because the value of the even numbers on the dice are more. Therefore, Jessica should play evens.
D
E(evens) = E(odds) because the different probabilities and values end up balancing out, creating a fair game. Therefore, Jessica may choose whichever she likes.
6

The table below shows the ages of houses to the nearest year in a neighborhood. Using the age of the houses as the random variable, X, which graph shows the probability distribution, PX(x), of a randomly chosen house?Age of HouseNumber of Houses115220325430

A
A probability distribution is shown. The probability of 1 is 0.16; 2 is 0.22; 3 is 0.28; 4 is 0.33.
Option A
B
A probability distribution is shown. The probability of 1 is 0.1; 2 is 0.2; 3 is 0.3; 4 is 0.4.
Option B
C
A probability distribution is shown. The probability of 1 is 0.65; 2 is 0.1; 3 is 0.12; 4 is 0.13.
Option C
D
A probability distribution is shown. The probability of 1 is 0.15; 2 is 0.2; 3 is 0.25; 4 is 0.3.
Option D
7

A high school student volunteers to present a report to the administration about the types of lunches students prefer. He surveys members of his class and records their choices. What type of sampling did the student use?

A
systematic random sampling
B
voluntary sampling
C
convenience sampling
D
stratified sampling
8

The graph below is used by company 2 to show the average monthly electric cost based on the electricity provider.How could the graph be redrawn so that the difference in monthly electric cost does not appear as great?

Question illustration
A
The scale on the y-axis could be changed to 0–150.
B
The scale on the y-axis could be changed to 100–120.
C
The interval on the y-axis could be changed to count by 1s.
D
The interval on the y-axis could be changed to count by 20s.
9

The human resources manager at a company records the length, in hours, of one shift at work, X. He creates the probability distribution below. What is the probability that a worker chosen at random works at least 8 hours?

Question illustration
A
0.62
B
0.78
C
0.84
D
0.96
10

Black Marble Points

S
Since E(black) = 0.24 and E(red) = 0.16, Seth should choose to play black marbles.
E
E(red) will be twice that of E(black), so Seth should choose to play red marbles.
S
Since E(red) = E(black), it is a fair game, so it doesn’t matter which color Seth chooses.
B
Both options will lose points because there are two ways to lose points and only one way to gain points. He should choose neither color.
11

The mean of a set of credit scores is and . Which statement must be true about z694?

Question illustration
A
z694 is within 1 standard deviation of the mean.
B
z694 is between 1 and 2 standard deviations of the mean.
C
z694 is between 2 and 3 standard deviations of the mean.
D
z694 is more than 3 standard deviations of the mean.
12

A manager records the number of hours, X, each employee works on his or her shift and develops the probability distribution below. Fifty people work for the manager. How many people work 4 hours per shift?Probability DistributionHours Worked: XProbability: P(X)30.14?50.1460.370.3680.06

A
0
B
1
C
2
D
4
13

Which of the following is a valid probability distribution?

A
Probability distribution A is shown. The probabilities of 1, 2, 3, 4, 5 and 6 are all 0.2.
Option A
B
Probability distribution B is shown. The probability of 1 is 0.1; 2 is 0.2; 3 is 0.3; 4 is 0.3; 5 is 0.2; 6 is 0.1.
Option B
C
Probability distribution C is shown. The probability of 1 is 0.1; 2 is 0.2; 3 is 0.4; 5 is 0.1; 6 is 0.1.
Option C
D
Probability distribution D is shown. The probability of 1 is 0.2; 2 is 0.1; 3 is 0.1; 4 is 0.5; 5 is 0.1.
Option D
14

The difference between an observational study and an experiment is that

A
in an observational study, only one group is studied, and in an experiment, two groups are studied.
B
in an observational study, the researchers do not control treatment, and in an experiment, they do.
C
in an experiment, cause-and-effect is analyzed, and in an observational study, it is not.
D
in an experiment, one group is studied over a short period of time, and in an observational study, the group is studied over a longer period of time.

Did you find these answers helpful?

More from this Course

Quiz
25 verified answers

Unit Test

Quiz
25 verified answers

Unit Test

Quiz
25 verified answers

Unit Test

Hypothesis Testing — Unit test Answers —…