For numbers 13-15, refer to the probability distribution below.
X 0 2 4 6 8
P(X)
13. What should be the value of k to complete the probability distribution?
A. B. C. D.
14. What is the mean of the probability distribution?
A. B. C. D.
15. What is the variance of the probability distribution?
A. B. C. D.
For number 16-20, refer to the following problem.
The time it takes for Grade 11 students in a certain school to complete a physical fitness test is normally distributed with a mean of 15 minutes and a standard deviation of 4 minutes.
16. What is the corresponding z-score of 12.5 minutes?
A. B. C. D.
17. What is the probability that a student completes the physical fitness test in less than 14 minutes?
A. B. C. D.
18. What is the longest time to complete the test of a student whose time belongs to the middle 60% of all recorded times?
A. B. C. D.
19. What is the fastest completion time of the students who belong to the longest 25% of all completion times?
A. B. C. D.
20. If the students who got the fastest 5% completion times will be exempted from the additional gym workout session, what is the slowest time that a student can have to qualify for the exemption?
A. B. C. D.
For numbers 21-25, refer to the following problem.
Suppose that the shelf life of Buko pies has a normal distribution with a mean of 36 hours and a standard deviation of 24 hours. Random samples of size 25 are taken.
21. What is the mean of the sampling distribution of the sample mean?
A. B. C. D.
22. What is the variance of the sampling distribution of the sample mean?
A. B. C. D.
23. What is the probability that the shelf life of the random sample of size 25 is less than 36.5 hours?
A. B. C. D.
24. What is the probability that the average shelf life of a random sample of size 25 is greater than 35 hours?
A. B. C. D.
25. What is the probability that the shelf life of the random sample of size 25 is between 35 to 37 hours?
A. B. C. D.
26. What is the best point estimate of the population mean?
A. B. C. D.
27. What is the range of values that contains the parameter value?
A. B. C. D.
28. Which of the following are the 95% confidence coefficients?
A. B. C. D.
29. When n = 30 and the population standard deviation is not known, what is the appropriate distribution?
A. B. C. D.
30. Given n = 100, X = 80, Ļ = 32, which of these is the point estimate of the population mean?
A. B. C. D.