The data presented in the table below resulted from an experiment Complete Solution

Question: #7909

Part 1 of 16 -

Question 1 of 23   1.0 Points
The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type?

Seed Type      Observed Frequencies
      Germinated   Failed to Germinate
   1   31   7
   2   57   33
   3   87   60
   4   52   44
   5   10   19

A.Yes, because the test value 16.86 is greater than the critical value of 13.28

B.Yes, because the test value 16.86 is less than the critical value of 14.86

C.No, because the test value 16.86 is greater than the critical value of 13.28

D.No, because the test value 13.28 is less than the critical value of 16.86

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Question 2 of 23   1.0 Points
A company operates four machines during three shifts each day. From production records, the data in the table below were collected. At the .05 level of significance test to determine if the number of breakdowns is independent of the shift.

    Machine
Shift   A   B   C   D
1   41   20   12   16
2   31   11   9   14
3   15   17   16   10

A.The number of breakdowns is dependent on the shift, because the test value 11.649 is less than the critical value of 12.592.
B.The claim that the number of breakdowns is independent of the shift cannot be rejected, because the test value 11.649 is less than the critical value of 12.592.
C.The number of breakdowns is dependent on the shift, because the p-value is .07.

D.The number of breakdowns is independent of the shift, because the test value 12.592 is greater than the critical value of 11.649.
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Part 2 of 16 -

Question 3 of 23 1.0 Points
In a simple linear regression analysis, the following sum of squares are produced:

= 500

= 100

= 400

The proportion of the variation in Y that is explained by the variation in X is:

A.50%

B.20%

C.80%

D.25%

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Question 4 of 23 1.0 Points
A single variable X can explain a large percentage of the variation in some other variable Y when the two variables are:

A.mutually exclusive

B.directly related

C.inversely related

D.highly correlated

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Question 5 of 23 1.0 Points
The city of Oakdale wishes to see if there is a linear relationship between the temperature and the amount of electricity used (in kilowatts). Based on the data in the table below, is there a significant linear relationship between temperature and the amount of electricity used? These data are also available in the worksheet temperature in the Excel workbook Temperature.xlsx.

Temperature.xlsx

Temperature (x) 73 78 85 98 93 81 76 105
Kilowatts (y) 680 760 910 1510 1170 837 600 1800

A.Yes, the sample correlation coefficient is equal to 0.981, which provides evidence of a significant linear relationship.
B.No, the sample correlation coefficient is equal to 0.098, which does not provide evidence of a significant linear relationship.
C.No, the sample correlation coefficient is equal to 0.981, which does not provide evidence of a significant linear relationship.
D.Yes, the sample correlation coefficient is equal to 0.878, which provides evidence of a significant linear relationship.
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Part 3 of 16 -

Question 6 of 23 1.0 Points
Two independent samples of sizes n1 = 50 and n2 = 50 are randomly selected from two populations to test the difference between the population means, . The sampling distribution of the sample mean difference, is:

A.normally distributed

B.approximately normal

C.chi-squared distributed with 99 degrees of freedom
D.t - distributed with 98 degrees of freedom

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Question 7 of 23   1.0 Points
Some defendants in criminal proceedings plead guilty and are sentenced without a trial, whereas others who plead innocent are subsequently found guilty and then are sentenced. In recent years, legal scholars have speculated as to whether sentences of those who plead guilty differ in severity from sentences for those who plead innocent and are subsequently judged guilty. Consider the data given below on defendants accused of robbery, all of whom, by the way, had previous prison records. At the .01 level of significance, do these data suggest that the proportion of all defendants in these circumstances who plead guilty and are sent to prison differs from the proportion who are sent to prison after pleading innocent and being found guilty?

    Plea
    Guilty   Not Guilty
Number judged guilty   n1 = 191   n2 = 64
Number sentenced to prison   x1 = 101   x2 = 56
Sample proportion   .529   .875

A.Yes, because the test value 2.58 is inside the interval (-4.94, 4.94)

B.Yes, because the test value -4.94 is outside the interval (-2.58, 2.58)
C.No, because the test value -4.94 is outside the interval (-1.96, 1.96)

D.No, because the test value -1.96 is inside the interval (-2.58, 2.58)

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Part 4 of 16 -

Question 8 of 23 1.0 Points
Smaller p-values indicate more evidence in support of the:

A.alternative hypothesis

B.the reduction of variance
C.null hypothesis

D.quality of the researcher

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Question 9 of 23 1.0 Points
Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.7 seconds. Suppose that you want to test the claim that the average time to accelerate from 0 to 60 miles per hour is longer than 7.7 seconds. What would you use for the alternative hypothesis?

A.H1: = 7.7 seconds

B.H1: > 7.7 seconds

C.H1: 7.7 seconds

D.H1: < 7.7 seconds

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Question 10 of 23 1.0 Points
The form of the alternative hypothesis can be:

A.two-tailed

B.one or two-tailed

C.one-tailed

D.neither one nor two-tailed

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Part 5 of 16 -

Question 11 of 23 1.0 Points
The t- distribution for developing a confidence interval for a mean has _____ degrees of freedom.

A.n

B.n - 2

C.n + 1

D.n - 1

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Question 12 of 23 1.0 Points
A food snack manufacturer samples 15 bags of pretzels off the assembly line and weighed their contents. If the sample mean is 10.0 and the sample standard deviation is 0.15, find the 95% confidence interval estimate for the true mean.

A.(9.96, 10.04)

B.(9.68, 10.32)

C.(9.97, 10.80)

D.(9.92, 10.08)

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Part 6 of 16 -

Question 13 of 23 1.0 Points
The mean of a probability distribution can be:

A.a positive number

B.a negative number

C.zero

D.all of the above

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Part 7 of 16 -

Question 14 of 23 1.0 Points
One of the requirements for a binomial experiment is that there must be a(n) _____ number of trials.

A.odd

B.random

C.infinite

D.fixed

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Part 8 of 16 -

Question 15 of 23 1.0 Points
A jar contains four white marbles, five red marbles, and six black marbles. If a marble is selected at random, find the probability that it is white or black .

A.2/15

B.2/3

C.1/5

D.2/5

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Part 9 of 16 -

Question 16 of 23 3.0 Points

Staples, a chain of large office supply stores, sells a line of desktop and laptop computers. Company executives want to know whether the demands for these two types of computers are dependent on one another. Each day's demand for each type of computers is categorized as Low, Medium-Low, Medium-High, or High. The data shown in the table below is based on 200 days of operation. Based on these data, can Staples conclude that demands for these two types of computers are independent? Test at the 5% level of significance.
          desktops
       low   med-low   med-high   high
    low   3   14   14   4   35
laptops   med-low   6   18   17   22   63
    med-high   13   16   11   16   56
    high   8   14   15   9   46
       30   62   57   51   200

What is the test value for this hypothesis test?

Answer: Round your answer to two decimal places.

What is the critical value for this hypothesis test?

Answer: Round your answer to two decimal places.

What is the conclusion for this hypothesis test? Choose one.

1. At the .05 level of significance, Staples can conclude that demands for these two types of computers are independent.
2. At the .05 level of significance, Staples can conclude that demands for these two types of computers are dependent.

Answer: Enter only a 1 or 2 for your answer.

Part 10 of 16 -

Question 17 of 23 1.0 Points

Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The marketing manager of a large supermarket chain would like to determine the effect of shelf space (in feet) on the weekly sales of international food (in hundreds of dollars). A random sample of 12 equal –sized stores is selected, with the following results:

Store   Shelf Space(X)   Weekly Sales(Y)
1   10   2.0
2   10   2.6
3   10   1.8
4   15   2.3
5   15   2.8
6   15   3.0
7   20   2.7
8   20   3.1
9   20   3.2
10   25   3.0
11   25   3.3
12   25   3.5

Based on these data, what are the least squares regression coefficients of the Y-intercept (a) and slope (b)?

Place your answers, rounded to 3 decimal places , in the blanks provided.

a = b =

Part 11 of 16 -

Question 18 of 23 1.0 Points

Two teams of workers assemble automobile engines at a manufacturing plant in Michigan. A random sample of 145 assemblies from team 1 shows 15 unacceptable assemblies. A similar random sample of 125 assemblies from team 2 shows 8 unacceptable assemblies.

If you are interested in determining if there is sufficient evidence to conclude, at the 10% significance level, that the two teams differ with respect to their proportions of unacceptable assemblies, what is the p-value associated with such a test of hypothesis?

Place your answer, rounded to 4 decimal places, in the blank. For example, .0123 would be a legitimate entry.

Part 12 of 16 -

Question 19 of 23 1.0 Points

A popular retail store knows that the purchase amounts by its customers is a random variable that follows a normal distribution with a mean of $30 and a standard deviation of $9.

What are the two dollar amounts, equidistant from the mean of $30, such that 90% of all customer purchases are between these values? Place your answers in the blanks provided. Do not include a dollar sign. For example, 14.25 would be a legitimate entry.

Lower value
Upper value

Part 13 of 16 -

Question 20 of 23 1.0 Points

A survey of 85 families showed that 36 owned at least one DVD player. Find the 99% confidence interval estimate of the true proportion of families who own at least one DVD player. Place your limits, rounded to 3 decimal places, in the blanks. Place the lower limit in the first blank and the upper limit in the second blank When entering your answer do not use any labels or symbols other than the decimal point. Simply provide the numerical values. For example, 0.123 would be a legitimate entry.

Part 14 of 16 -

Question 21 of 23 1.0 Points

Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
If a gambler rolls two dice and gets a sum of four, he wins $10; and if he gets a sum of three, he wins $25. The cost to play the game is $5. What is the expectation of this game?

Place your answer, rounded to two decimal places, in the blank. When entering your answer do not use a dollar sign. However, if the expected payoff is negative be sure to use a minus sign. For example, -1.23 would be a legitimate entry.

Part 15 of 16 -

Question 22 of 23 1.0 Points

At a university, the average cost of books per student has been $550 per student per semester. The Dean of Students believes that the costs are increasing and that the average is now greater than $550. He surveys a sample of 40 students and finds that for the most recent semester their average cost was $630 with a standard deviation of $120. What is the test value for this hypothesis test?

Test value: Round your answer to two decimal places as necessary.

Part 16 of 16 -

Question 23 of 23 1.0 Points

A restaurant menu has a price-fixed complete dinner that consists of an appetizer, entrée, beverage, and dessert. You have a choice of five appetizers, ten entrees, three beverages, and six desserts. How many possible complete dinners are possible? Place your answer, as a whole number—no decimal places—in the blank. For example 176 would be a legitimate entry

Solution: #7903

The data presented in the table below resulted from an experiment Complete Solution

17) a = 1.480 b = 0.074 18) 0.2460...