Test Name: Final Exam Practice #2 1. Temperatures in degrees Kelvin of various sites on the moon are an example of which type of data? (2 Points) 2. If a participant begins a study but fails to complete it, then that participant is a(n) _______. Fill in the blank with the most appropriate word. (2 Points) 3. Consider the following frequency table representing the distribution of hours students spend on homework in a week. Hours Students Spend on Homework in a Week Class Frequency 9−¿16 4 17−¿24 7 25−¿32 8 33−¿40 13 41−¿48 3 Step 1. Determine the cumulative frequency for the third class. (2 Points) Step 2. Determine the cumulative frequency for the second class. (1 Points) Answer: A) Qualitative B) Parameter C) Quantitative D) Inferential Answer: A) Informed Consent B) Participation Bias C) Bias D) Non-Sampling Error(s) E) Researcher Bias F) Processing Error(s) G) Sampling Error(s) H) Non-Adhere(s) I) Dropout J) Confounding Variable(s)
Transcript
Test Name: Final Exam Practice #2
1. Temperatures in degrees Kelvin of various sites on the moon are an example of which type of data? (2 Points)
2. If a participant begins a study but fails to complete it, then that participant is a(n) _______. Fill in the blank with the most appropriate word. (2 Points)
3. Consider the following frequency table representing the distribution of hours students spend on homework in a week.
Hours Students Spend on Homework in a WeekClass Frequency
9−¿16 417−¿24 725−¿32 833−¿40 1341−¿48 3
Step 1. Determine the cumulative frequency for the third class. (2 Points) Step 2. Determine the cumulative frequency for the second class. (1 Points)
Answer: A) Qualitative
B) Parameter
C) Quantitative
D) Inferential
Answer: A) Informed Consent B) Participation Bias C) Bias
4. The following histogram represents the distribution of scores on a ten point quiz.
Step 1. Which score has the highest frequency? (2 Points)
Step 2. What is the frequency corresponding to a score of 4? (1 Points) Step 3. What is the total number of people who made a score between 6 and 8 inclusive? (1 Points)
5. Pick the graph that best describes the following distribution shape:Symmetrical
(3 Points)
Answer:
A) B) C) D)
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6. Find the mean, median, and mode of the following data. Use the rounding rules for calculating the mean and median. Separate multiple answers with commas, if necessary.
Rate of Fatal Alcohol Impaired Car Crashes per 100 Million Vehicle Miles of Travel
7. Consider the following data:9 ,14 ,15 ,3 ,8 ,11
Step 1. Find the value of the sample variance. Round your answer to one decimal place. (1 Points) Step 2. Find the value of the sample standard deviation. Round your answer to one decimal place. (1 Points) Step 3. Find the value of the range. (1 Points)
8. Suppose that a Senate committee is composed of 23 Senators of whom 4 are women. What proportion of the committee are women? Use the rounding rule for calculating the proportion.
(3 Points)
9. Given the following data, find the percentile of a weight of 8.3 pounds.
10. Given the following graph, where the mean score is marked, which value best represents the z -score shown?
(2 Points)
11. Evaluate the following expression.12!
4 !8 !
(3 Points)
12. Kenisha is picking out some movies to rent, and she has narrowed down her selections to 4 mysteries, 6 horror films, 7 dramas, and 3 comedies. How many different combinations of 9 movies can she rent if she wants all 7 dramas?
(3 Points)
13. You are going to play mini golf. A ball machine that contains 19 green golf balls, 20 red golf balls, 25 blue golf balls, and 18 yellow golf balls, randomly gives you your ball. What is the probability that you end up with a red golf ball? Express your answer as a simplified fraction or a decimal rounded to three decimal places.
(2 Points)
14. Determine whether the following value could be a probability.0.7
(2 Points)
15. Suppose you like to keep a jar of change on your desk. Currently, the jar contains the following:
24
Pennies 29 Dimes
22
Nickels 8 Quarters
What is the probability that you reach into the jar and randomly grab a dime and then, without replacement, another dime? Write your answer as a fraction or a decimal number rounded to three decimal places. (2 Points)
Answer: A) z=1.61 B) z=0
C) z=−1.69
Answer: A) Yes B) No
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16. Classify the following as either a discrete random variable or a continuous random variable.A phone usage study records the time spent on the phone each day for 189 randomly selected individuals.
(3 Points)
17. Find the standard deviation of the following data. Round your answer to one decimal place.
x 5 6 7 8 9P (X=x ) 0.1 0.2 0.3 0.2 0.2
(5 Points)
18. The life of light bulbs is distributed normally. The variance of the life time is 625 and the mean lifetime of a bulb is 520 hours. Find the probability of a bulb lasting for at most 565 hours. (Round your answer to 4 decimal places)
(5 Points)
19. Find the value of z such that 0.1 of the area lies to the left of z. (Round your answer to 2 decimal places.) (5 Points)
20. The mean cost of a five pound bag of shrimp is 42 dollars with a variance of 49. If a sample of 44 bags of shrimp is randomly selected, what is the probability that the sample mean would be less than 44.3 dollars? (Round your answer to 4 decimal places)
(5 Points)
21. Thompson and Thompson is a steel bolts manufacturing company. Their current steel bolts have a mean diameter of 130 millimeters, and a standard deviation of 5. If a random sample of 34 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by less than 0.2 millimeters? (Round your answer to 4 decimal places)
(5 Points)
22. A research scholar wants to estimate the mean number of school children (in thousands) who read below their grade level in a major city in Texas. He believes that the mean is 28.5. Assume the standard deviation is known to be 11.4. How large a sample would be required in order to estimate the mean number of school children (in thousands) who read below their grade level at the 99% confidence level with an error of at most 0.55? (Round your answer up to the next integer)
(5 Points)
23. A random sample of 22 fields of durum wheat has a mean yield of 49.8 bushels per acre and standard deviation of 7.92 bushels per acre. Determine the 98% confidence interval for the true mean yield. Assume the population is approximately normal. Step 1. Find the critical value that should be used in constructing the confidence interval. (Round answer to 3 decimal places) (3 Points)
Answer: A) Discrete
B) Continuous
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Step 2. Construct the 98% confidence interval. (Round answer to 1 decimal place) (2 Points)
24. A lumber company is making boards that are 2611 millimeters tall. If the boards are too long they must be trimmed, and if they are too short they cannot be used. A sample of 34 boards is taken, and it is found that they have a mean of 2615.4 millimeters with a standard deviation of 14. Is there evidence at the 0.02 level that the boards are too long and need to be trimmed? Step 1. State the hypotheses: (2 Points)
Step 2. Find the value of the z test statistic. (Round your answer to 2 decimal places.) (2 Points) Step 3. Specify if the test is one-tailed or two-tailed. (1 Points)
Step 4. Find the P value of the z test statistic. (Round your answer to 4 decimal places.) (2 Points) Step 5. Determine the value of the level of significance. (2 Points) Step 6. Determine the conclusion. (1 Points)
Lower Bound:
Upper Bound:
H 0 :
H a :
A) One-Tailed Test B) Two-Tailed Test
A) Reject Null Hypothesis B) Fail to Reject Null Hypothesis
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25. Consider the relationship between the number of bids an item on eBay received and the item's selling price. The following is a sample of 5 items sold through an auction.
Price in Dollars 23 35 38 41 47Number of Bids 13 14 15 17 18
Step 1. Draw a scatter plot of the given data. (3 Points)
Step 2. Estimate the correlation in words: positive, negative, no correlation. (3 Points)
Step 3. Calculate the correlation coefficient, r. Please round your answer to three decimal places. (4 Points)
