Download Final 2010-B Past Papers Stat

Form No.(
).
Jordan University.
Faculty of Pharmacy.
Biostatistics and pharmaceutical statistics.
Name:
No.:
Section time:
You have 47 multiple choice questions (chose the one best answer)
and one essay question should be answered on the back of last page.
(Q1-Q3) the following is the 5 number summary of the content of active drug in a sample of tablets,
answer the following three questions
132
160
190
210
270
1. What is the 75% percentile?
a. 190
b. 210
c. 270
d. 132
e. 160
2. The mean of the above values
a. 132
b. 160
c. 190
d. 192.4
e. There is no sufficient information
3. The range is
a. 190
b. 132
c. 138
d. 160
e. None of the above
4. Which of the followings is a measure for central tendency?
a. Interquartile range
b. First quartile
c. Second quartile
d. Third quartile
5. Suppose that the first quartile Q1 and the Interquartile range IQR of the sample data are equal, and that the
third quartile Q3 equals 50. Then the interqurtile range of the sample data equals :
a. 18
b. 25
c. 32
d. None
6. In a certain population, the probability is 0.45 that a randomly selected patient will be male. The probability
is 0.75 that a patient with heart disease. What is the probability that a patient randomly selected from the
population will be male and have heart disease?
a. 0.45
b. 0.75
c. 0.34
d. 0.30
e. None
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7. Given the normally distributed variable X with a variance of 9 and P(X230) = 0.7157, find out μ.
a. 5.1310
b. 0.7157
c. 231.7
d. 228.29
e. None
8. For a binomial distribution of the results of a 20 Bernoulli trials with a success rate of 0.4, what
is the mean?
a. 20
b. 20.4
c. 8
d. 19.6
e. None
9. What is the percentage area enclosed between the perpendicular erected at the mean (μ), that
erected at (z=2), the z axis and the standard normal distribution curve?
a. 47.7%
b. 68%
c. 34%
d. 32%
e. None
(Q10-11) Use the following graph representing normal distributions to answer questions
10. Which is the normal distribution with the highest mean?
a. A
b. B
c. C
d. μA= μB = μC
11. Which is the normal distribution with the largest standard deviation?
a. A
b. B
c. C
d. σA= σB = σC
12. What is the value of the mean of a standard normal distribution?
a. 100
b. 1
c. 0
d. Could assume any value depending on the property measured and population
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13. In the assay content of Aspirin tablets, the mean was 30 mg and standard deviation was 3mg,
find out z for the content 27mg assuming that the assay content is normally distributed
a.
b.
c.
d.
e.
3
-3
-1
1
None
14. A population consists of 15 pharmacy students. If we want to select 5 of them to represent the
students in the faculty council. How many possible samples can we get?
a. 2.6 * 1010
b. 759375
c. 3003
d. None
15. When rejecting a null hypothesis, the calculated p value should be less than:
a. β
b. z
c. t
d. α
16. Comparing a one sided test to a two sided test, if α=0.05, the rejection region (area) is:
a. Equal for the one sided and two sided tests
b. Larger for the one sided test
c. Larger for the two sided test
17. The test statistic that can be used in paired comparison assuming normal distribution and known
population variance is:
a. α
b. β
c. z
d. t
18. If the p value for a hypothesis testing is less than 0.005, then the z value is:
a. = 0
b. ≤ 1.96
c. ≤ 2.57
d. ≥ 2.57
19. The t distribution approaches the normal distribution as:
a. Sample size decreases
b. When n-1 equals the df
c. df approaches infinity
d. All of the previous options are true
20. Which of the following is true regarding the confidence interval
a. As we increase the standard deviation, the interval will be narrower
b. As we increase the confidence level, the interval will be narrower
c. As we increase the sample size (n), the interval will be narrower
d. All of the above are true
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(Q21-23) Suppose it is known that the height of a certain population of individuals are approximately
normally distributed with a mean of 120 inches and a standard deviation of 15 inch.
21. What is the probability that a person picked at random from this group and his height will be
less than 125?
a.
b.
c.
d.
e.
0.83
0.99
0.33
0.63
None
22. What is the probability that a random sample of 50 individuals will have a mean height less 122
inches?
a. 0.55
b. 0.83
c. 0.98
d. 0.94
e. None
23. What is the probability that a random sample of 50 individuals, their total heights be more than
6100 inches is:
a. 0.63
b. 0.83
c. 0.17
d. 0.37
e. None
(Q24-27) Assume that a tableting machine produces normally distributed Aspirin tablets with a mean of
650 mg and a standard deviation of 9 mg. A sample of 9 tablets was randomly taken and their
mean was 640 Answer the following questions
24. What is the mean of a sampling distribution for a sample size of 9?
a. 650
b. 640
c. 660
d. 0
e. None
25. What is the standard error for the taken sample size (n=9)?
a. 1
b. 1.73
c. 3
e. 9
d. 0.33
26. The 95% confidence interval for the mean of the sample in the question:
a. -1.96 – 1.96
b. 641 – 659
c. 634.1 – 645.9
d. 631 – 649
e. None
27. If we calculated the 99% CI instead of the 95% CI in the previous question, it will be:
a. Narrower
b. Wider
c. The same
d. t test
e. None
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Q(28- 31) 6 students were selected from a class, their mean in the exam was 75 and their standard
deviation was (5.5). Depending on these data answer the following 4 questions
28. The number of degrees of freedom for this sample is:
a. 7
b. 6
c. 5
d. 4
e. none
29. What is the critical value (t) for the 90% CI of these data
a. 2.015
b. 1.96
c. 2.576
d. 1.645
e. none
30. A 90% CI for the population mean weight is:
a. 73.04 – 76.95
b. 70.60 – 79.40
c. 70.48 – 79.52
d. 69.50 – 80.50
e. None
31. The test statistic value for testing null hypothesis H0: μ=72 is:
a. 1.536
b. -1.34
c. 1.34
d. -1.536
e. 0.545
Q(32- 37)Assume that the weight of carbamazepine tablets have a mean weight of 325 mg, a standard
deviation of 3 mg and are normally distributed. Answer the following questions
32. A sample of 50 tablets from a new batch showed a mean of 324 mg. What is the critical value
for testing if the mean is less than 325 at α=0.05?
a. 1.645
b. -1.96
c. 1.96
d. 2.796
e. -1.645
33. The standard error of the mean in the sample mentioned is previous question is:
a. 0.05
b. 0.42
c. 0.73
d. 0.58
e. -1.96
34. The value of the test statistic (z test) for the sample in the question 32 is:
a. -3.45
b. -0.59
c. -1.63
d. -2.38
e. -1.39
35. The p value associated with the above test statistic (question 34) is:
a. 0.2776
b. 0.0003
c. 0.0516
d. 0.009
e. 0.0823
36. The p value determined in the previous question 35 is:
a. Left sided
b. Right sided c. Two tailed
d. Two sided
37. The result of the testing is:
a. That the mean is significantly less than 325
b. That the mean is more than 325
c. That the mean is not significantly less than 325
d. b and c
e. a and c
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Q(38-41)One pharmacy student is interested in studying the level of ALT enzyme in the students of
faculty of pharmacy. A simple random sample of 9 individuals was taken their mean value of
ALT level was 55 IU. Assume that this sample comes from a population whose ALT values are
approximately normally distributed with a known variance of 25. If you know that the mean of
ALT American students' value is 50 IU. Can we conclude that the mean value of students in the
faculty pharmacy is equal to that of American Students at significant level of 0.05?
38. To answer the above question the following Null and alternative hypotheses should be
constructed
a. H0: μ ≥ 50, vs HA:  < 50.
b. H0:  ≤ 50.vs HA :  > 50.
c. H0:   50, vs HA:  = 50.
d. H0:  = 50, vs HA:   50.
39. The critical rejection region
a. Z [-1.96 – 1.96]
b. Z ≥ 1.96, or Z ≤ -1.96
c. t [ -2.262 – 2.262]
d. t ≥ 2.262, or t ≤-2.262
e. None
40. Test statistic value
a.
b.
c.
d.
e.
-0.6
0.6
3
-3
None
41. The final conclusion and decision
a. Reject Null hypothesis,  the values of the pharmacy students are equal to that of American students
b. Reject Null hypothesis,  the values of the pharmacy students are different from that of American
students)
c. Accept Null hypothesis  the values of the pharmacy students are equal to that of American students
d. Accept Null hypothesis  the values of the pharmacy students are different from that of American
students)
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Q(41- 47)In a study to investigate the effect of Salvia extract on blood glucose level, one group of rats was
treated with the extract and the other was used as control group (not treated).
The average blood glucose level of the treated (n=6 rats) was 12.4 mM with standard deviation
of 6.7 mM. The average glucose level of the control um-treated (10 subjects) was 16.3 with a
standard deviation of 5.2
Assuming that population variances are unknown and equal. Find out if there is a significant
effect of the extract on blood glucose at level of significance 0.1
In your answer show the following in the provided space
42. To answer the above question the following Null and alternative hypotheses should be
constructed
a. H0: 1- 2 ≥ 0. vs HA: 1- 2 < 0.
b. H0: 1- 2 ≤ 0.vs HA : 1- 2 > 0.
c. H0: 1- 2 = 0, vs HA: 1- 2  0.
d. H0: 1- 2  0, vs HA: 1- 2 = 0.
43. Degree of freedom in this case
a. 15
b. 14
c. 10
d. 6
e. 16
44. Pooled standard deviation =
a. 243.4
b. 5.78
c. 33.42
d. 224.5
e. None
45. The critical rejection region
a. Z [-1.645 – 1.645]
b. t ≥ 1.645, or t ≤ -1.645
c. t ≥ 1.761, or t ≤ -1.761
d. t [-1.761 – 1.761]
e. None
46. Test statistic value for this case
a. Z-value = ± 1.645
b. t-value = ± 1.761
c. t-value = ± 1.31
d. Z-value = ± 1.31
47. The final conclusion and decision
a. Accept Null hypothesis  There is no significant effect of salvia on blood glucose
b. Accept Null hypothesis  There is significant effect of salvia on blood glucose
c. Reject Null hypothesis,  There is no significant effect of salvia on blood glucose
d. Reject Null hypothesis,  There is significant effect of salvia on blood glucose
48.
Mention the central tendency and dispersion parameters (on the back the last
page)
Good luck
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P( x)   n  p x (1  p) n  x
 x
n Cx 
n!
x!(n  x)!
µ = np
2 = np(l — p)
z
x


t
X t*

z
x 
s/ n

X  z*
n



n

( x1  x 2 )  ( 1   2 ) 0
 12
n1

 22
n2
2
2
(
n

1
)
s

(
n

1
)
s
1
2
2
s 2p  1
n1  n2  2

t



( x1  x 2 )  ( 1   2 ) 0
s 2p
n1

s 2p
n2
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