Record your answers and work in the space below each problem
Question # 00326281
Posted By:
Updated on: 06/28/2016 12:26 AM Due on: 06/28/2016
Page 1 of 3
Quiz 2
Stat 200 (Clary)
(6382, 2152)
Instructions: Record your answers and work in the space below each problem. Be sure to record
the final answer next to “Answer” and show all your calculation steps or assumptions under
“Work.” You can type in your calculations, use the equation tool, or insert images of your
handwritten calculations. If you have a tablet with a stylus, it may even be possible to write
directly into the table cell. Whatever you do, make sure it is clear and neat. Thanks.
Remember to add your last and first name to the end of the file name and upload your
answers here (e.g., FILENAME.LASTNAME.FIRSTNAME.docx) before submitting.
Proble
m
Number
#1
(5 pts)
Problem and Solution
1. Forty percent of the faculty teach online classes and 25% of the faculty teach part
time. Of the part time faculty, 60% have taught an online class. Let A = event that a
faculty member teaches an online class and B = event that a faculty member is part time.
a. Find P(A AND B).
b. Find P(B|A).
c. Find P(A OR B).
d. Using an appropriate test, show whether A and B are independent.
e. Using an appropriate test, show whether A and B are mutually exclusive.
Answer:
Work:
#2
(5 pts)
Height and weight are two measurements used to track a child’s development. The World Health
Organization measures child development by comparing the weights of children who are the
same height and the same gender. In 2009, weights for all 80 cm girls in the reference population
had a mean ? = 10.2 kg and standard deviation ? = 0.8 kg. Weights are normally distributed. X ~
N(10.2, 0.8). Calculate the z-scores that correspond to the following weights and interpret them.
a. 11 kg
Page 2 of 3
b. 7.9 kg
c. 12.2 kg
Answer:
Work:
#3
(5 pts)
In 2015, the average length of Hillary Clinton’s emails were 174 words, with a standard
deviation of 55 words. Suppose we randomly pick 38 of her emails from 2015.
a. In words, ? = _____________
b. In words, X ¯ = _____________
c. X ¯ ~ _____(_____,_____)
d. The IQR for X ¯ =
Answer:
Work:
#4
(5 pts)
The average length of a maternity stay in a U.S. hospital is said to be 2.4 days with a standard
deviation of 0.9 days. We randomly survey 80 women who recently bore children in a U.S.
hospital.
a. In words, X = _____________
b. In words, X ¯ = ___________________
c. X ¯ ~ _____(_____,_____)
d. In words, ?X = _______________
e. ?X ~ _____(_____,_____)
f. Is it likely that an individual stayed more than five days in the hospital? Why or why not?
g. Is it likely that the average stay for the 80 women was more than five days? Why or why not?
h. Which is more likely:
1. An individual stayed more than five days.
2. The average stay of 80 women was more than five days.
Page 3 of 3
i. If we were to sum up the women’s stays, is it likely that, collectively they spent more than a
year in the hospital?
Answer:
Work:
Quiz 2
Stat 200 (Clary)
(6382, 2152)
Instructions: Record your answers and work in the space below each problem. Be sure to record
the final answer next to “Answer” and show all your calculation steps or assumptions under
“Work.” You can type in your calculations, use the equation tool, or insert images of your
handwritten calculations. If you have a tablet with a stylus, it may even be possible to write
directly into the table cell. Whatever you do, make sure it is clear and neat. Thanks.
Remember to add your last and first name to the end of the file name and upload your
answers here (e.g., FILENAME.LASTNAME.FIRSTNAME.docx) before submitting.
Proble
m
Number
#1
(5 pts)
Problem and Solution
1. Forty percent of the faculty teach online classes and 25% of the faculty teach part
time. Of the part time faculty, 60% have taught an online class. Let A = event that a
faculty member teaches an online class and B = event that a faculty member is part time.
a. Find P(A AND B).
b. Find P(B|A).
c. Find P(A OR B).
d. Using an appropriate test, show whether A and B are independent.
e. Using an appropriate test, show whether A and B are mutually exclusive.
Answer:
Work:
#2
(5 pts)
Height and weight are two measurements used to track a child’s development. The World Health
Organization measures child development by comparing the weights of children who are the
same height and the same gender. In 2009, weights for all 80 cm girls in the reference population
had a mean ? = 10.2 kg and standard deviation ? = 0.8 kg. Weights are normally distributed. X ~
N(10.2, 0.8). Calculate the z-scores that correspond to the following weights and interpret them.
a. 11 kg
Page 2 of 3
b. 7.9 kg
c. 12.2 kg
Answer:
Work:
#3
(5 pts)
In 2015, the average length of Hillary Clinton’s emails were 174 words, with a standard
deviation of 55 words. Suppose we randomly pick 38 of her emails from 2015.
a. In words, ? = _____________
b. In words, X ¯ = _____________
c. X ¯ ~ _____(_____,_____)
d. The IQR for X ¯ =
Answer:
Work:
#4
(5 pts)
The average length of a maternity stay in a U.S. hospital is said to be 2.4 days with a standard
deviation of 0.9 days. We randomly survey 80 women who recently bore children in a U.S.
hospital.
a. In words, X = _____________
b. In words, X ¯ = ___________________
c. X ¯ ~ _____(_____,_____)
d. In words, ?X = _______________
e. ?X ~ _____(_____,_____)
f. Is it likely that an individual stayed more than five days in the hospital? Why or why not?
g. Is it likely that the average stay for the 80 women was more than five days? Why or why not?
h. Which is more likely:
1. An individual stayed more than five days.
2. The average stay of 80 women was more than five days.
Page 3 of 3
i. If we were to sum up the women’s stays, is it likely that, collectively they spent more than a
year in the hospital?
Answer:
Work:
-
Rating:
/5
Solution: Record your answers and work in the space below each problem