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Michael\'s teacher informed him that his score of 98 on the last Algebra test co

ID: 3234318 • Letter: M

Question

Michael's teacher informed him that his score of 98 on the last Algebra test corresponded to a z-score of -2.12. Which of the following is the best interpretation of Michael's result?

Question 1 options:

Michael did very well on this test in relation to the class.

Michael did very poorly on this test in relation to the class.

Michael scored somewhat above average in relation to the class.

Michael scored a little below average in relation to the class.

Michael's score was very close to the class average.

A portion of people in the population claim to have certain psychic powers. Specifically some people have claimed to have experienced astral projections. A group of psychologists believe that people who have experienced astral projection also have a higher likelihood of having experienced premonitions. In order to test this claim two procedures have been proposed:

Plan A: Take a sample of people who have experienced astral projection and measure the proportion of people in this group who have also experienced premonitions. Take another sample of people who have not experienced astral projection and measure the proportion of people who have experienced premonitions. Compare the two proportions.

Plan B: Take a random sample of people and compare the proportion of people who have experienced both astral projection and premonitions with the proportion of people who have experienced only premonitions.

Which of the following methods is best for testing the claim made by the psychologists?

Question 2 options:

Choose Plan A over Plan B.

Choose Plan B over Plan A.

Both plans will be equally effective in producing valid results.

Neither plan will be effective in producing valid results.

The plans cannnot be evaluated based on the information given.

Moren's Department Store has a special sale whereby each customer, upon checkout, chooses a random ticket that is labeled 5%, 15%, or 25%. The customer is then allowed to take a discount of that amount from the total sale. ten percent of the tickets are labeled 25%, 20% are labeled 15%, and the remaining are labeled 5%. Excluding sales tax, what is the expected actual sale for a customer wishing to purchase $200 worth of merchandise?

Question 6 options:

$134

$154

$170

$182

$190

From a sample of 200 residents of the city of Springfield, the income of each person was recorded. However, it was found that one of the values was considerably higher than the other values in the sample. If this high value is removed from the data set, which of the following values will be guaranteed to remain unaffected?

Question 7 options:

Mean

Median

Mode

Standard Deviation

Range

Doctor's are experimenting with a drug to control stomach disorders. However, one of the side effects of the drug is an increase in heart rate. In a clinical trial several patients with stomach disorders were given the drug. Their heart rates were recorded before the drug was administered and then measured again 1 hour later. The data is given below.

Patient

Heart Rate Before (bpm)

Heart Rate After (bpm)

1

88

89

2

90

97

3

79

81

4

91

99

5

77

79

6

80

84

7

88

98

8

80

78

What is the number of degrees of freedom associated with the appropriate t-test for testing whether the heart rates for patients actually increase with the use of the experimental drug?

Question 8 options:

2

7

8

14

15

Coastal College wants to determine whether smoking has decreased on campus over the past five years. According to a survey done five years previously, among 400 randomly selected students, 123 were smokers. The survey is done again in the present day, and among 600 randomly selected students, 155 were smokers. If the null hypothesis is that the proportion of smokers is the same, tested against the alternate hypothesis that the proportion has decreased, what would be the value of the appropriate z-statistic for this test?

Question 10 options:

0.845

1.433

1.700

2.158

2.949

The following two-way contingency table represents results from a test as to whether taking a test prep course has a positive effect on students wanting to pass the test.

Passed Test

Failed Test

Took test prep course

57

23

Did not take test prep course

61

77

If the null hypothesis is that the test prep course has no effect on whether students pass the test, which of the following values gives the expected number of people taking the test prep course who would pass the test?

Question 14 options:

36.7

43.3

57.0

63.3

74.7

The Soft Light Electric Company is producing 40-watt lightbulbs. To test whether the bulbs are being produced correctly, the production manager has sampled 200 random 40-watt bulbs in order to test the null hypothesis that the mean wattage is p. = 40 watts against the alternate hypothesis that the mean wattage is not equal to 40 watts. The sample mean was determined to be 40.117 watts, with a sample standard deviation 0.966. What is the p-value of the appropriate test statistic?

Question 16 options:

0.0441

0.0478

0.0883

0.1211

0.4558

A mid-size college has several professors in the Chemistry and Biology departments. The number of years of experience for the professors in the departments are to be compared:

Chemistry

1

1

4

5

8

15

22

Biology

0

1

2

5

6

8

17

For which of the measurements does the Chemistry department have the larger value?

   I. Range

II. Standard Deviation

III. Interquartile Range

Question 18 options:

I only

II only

III only

I and II only

I, II, and III

A binomial experiment, which has the probability of success for one trial p = 0.63, is being observed, and 70 trials are preformed. Binomial probabilities for various outcomes can be computed. However, they can also be computed using another distribution. In this case, which distribution could be used to approximate this particular distribution?

Question 19 options:

Uniform distribution with mean 44.1

Geometric distribution with p = 0.63

Chi-square distribution with 69 degrees of freedom

t-distribution with 69 degrees of freedom

Normal distribution with mean 44.1

Michael did very well on this test in relation to the class.

Michael did very poorly on this test in relation to the class.

Michael scored somewhat above average in relation to the class.

Michael scored a little below average in relation to the class.

Michael's score was very close to the class average.

Explanation / Answer

Question 1:

Any z score below -2 is considered as unusually low. Therefore, correct option is:

Michael did very poorly on this test in relation to the class.

Question 2: In Plan B, he is comparing people who have experienced astral projection also have a higher likelihood of having experienced premonitions, which was his claim. Therefore, correct option is:

Choose Plan B over Plan A.

Question 6: Consider the following table:

The expected discount is xP(x) = 9%

The expected actual sale for a customer wishing to purchase $200 worth of merchandise is:

200(1-0.09)=$182

Therefore, correct option is: $182

Question 7: Since there was only one extreme value, the mode will be unaffected because mode is most occurred value and if we remove only one extreme value, the mode will be unaffected. Therefore, correct option is:

Mode

Question 8: df=n-1=8-1=7

Therefore, correct option is:

7

x P(x) x P(x) 25 0.1 2.50 15 0.2 3.00 5 0.7 3.50 Sum 1.00 9.0