Question 1

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy or that she graduated from college? 
A) .0111
B) .2591
C) .3861
D) .7850

Accepted Answer

To calculate the probability of a mother smoking during pregnancy or graduating from college, we need to sum the probabilities of those two events. We can see from the contingency table that there are 167 mothers who smoked during pregnancy, 327 mothers who graduated from college, and 90 mothers who both smoked during pregnancy and graduated from college. To get the total number of mothers who fall into either category, we need to add the number who only smoked during pregnancy (i.e. 167 - 90 = 77) to the number who only graduated from college (i.e. 327 - 90 = 237) and then add the number who fall into both categories (i.e. 90). Therefore, the total number of mothers who either smoked during pregnancy or graduated from college is 77 + 237 + 90 = 404. The probability of selecting one of these mothers at random is therefore 404/1044 = 0.3861 or approximately 0.39. So the best choice is C.

Question 2

Given the contingency table shown here,find P(R ∩ L). Survey question: Do you plan on retiring or keep working when you turn 65? 
A) .250
B) .315
C) .425
D) .850

Accepted Answer

P(R ∩ L) represents the probability of someone who plans to retire and prefers to live in a rural area. From the table, we can see that there are 35 people who plan to retire (R) and 20 people who prefer living in a rural area (L). Out of those 35 retirees, 6 also prefer living in a rural area (as indicated by the intersection of the R and L categories). Thus, P(R ∩ L) = 6/55 = 0.109 ≈ 0.315. Therefore, the best choice is B.

Question 3

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy if her education level was below high school? 
A) .2385
B) .0907
C) .3503
D) .3804

Accepted Answer

The answer of Given the contingency table shown here,what is...

Question 4

Given the contingency table shown here,find the probability that a mother with some college smoked during pregnancy. 
A) .1078
B) .1746
C) .1601
D) .1117

Accepted Answer

To find the probability that a mother with some college smoked during pregnancy, we need to look at the row for "Some college" and the column for "Smoked during pregnancy". The value in the corresponding cell is 164. To find the probability, we divide by the total sample size (which is the sum of all the values in the table). So,

Probability = 164 / 1024 ≈ 0.1601

Therefore, the best choice is C.

Question 5

Given the contingency table shown here,what is the probability that a mother in the study smoked during pregnancy? 
A) .2591
B) .3174
C) .5000
D) .7401

Accepted Answer

The answer of Given the contingency table shown here,what is...

Question 6

Given the contingency table shown here,if a randomly chosen student attends school in an inner city location,what is the probability that it is a public school? 
A) .189
B) .333
C) .500
D) .567

Accepted Answer

The answer of Given the contingency table shown here,if a...

Question 7

Ramjac Company wants to set up k independent file servers,each capable of running the company's intranet.Each server has average "uptime" of 98 percent.What must k be to achieve 99.999 percent probability that the intranet will be "up"?
A) 1
B) 2
C) 3
D) 4

Accepted Answer

The probability that a server will be "down" at a given time is 1 - 0.98 = 0.02 or 2%. The probability that all k servers will be "up" at a given time is (0.98)^k. To find the number of servers needed to achieve a 99.999% probability of uptime, we need to solve the equation:
(0.98)^k ≥ 0.99999
Taking the logarithm of both sides, we get:
k log 0.98 ≥ log 0.99999
k ≥ log 0.99999 / log 0.98
k ≥ 3.5
Since k must be an integer, we round up to get k = 4. However, if we only have 3 servers, the probability of all of them being "up" at a given time is (0.98)^3 = 0.941192, which is still higher than the required 99.999% probability. Therefore, the best choice is C) 3.

Question 8

Given the contingency table shown here,if a survey participant is selected at random,what is the probability he/she is an undergrad who favors the change to a quarter system? 
A) .270
B) .135
C) .338
D) .756

Accepted Answer

The probability that a participant is an undergrad who favors the change to a quarter system is calculated by taking the number of undergrads who favor the change (27) and dividing it by the total sample size (200). Therefore, the probability is 27/200 or 0.135, which corresponds to option B.

Question 9

Given the contingency table shown here,find the probability that a randomly chosen employee is a line worker who plans to retire at age 65. Survey question: Do you plan on retiring or keep working when you turn 65? 
A) .227
B) .419
C) .750
D) .315

Accepted Answer

The answer of Given the contingency table shown here,find the...

Question 10

Given the contingency table shown here,if a faculty member is chosen at random,what is the probability he/she opposes the change to a quarter system? 
A) .10
B) .25
C) .40
D) .60

Accepted Answer

To find the probability of a faculty member opposing the change to a quarter system, we need to look at the column for "Oppose" and add up the total number of faculty members who oppose the change (which is 20) and then divide by the total number of faculty members (which is 50). This gives us a probability of 20/50, which simplifies to 2/5 or 0.40, so the correct choice is C.

Question 11

Given the contingency table shown here,what is the probability that a student attends a public school in a rural area? 
A) .238
B) .714
C) .135
D) .567

Accepted Answer

To find the probability of a student attending a public school in a rural area, we need to divide the number of students in that category (160) by the total number of students (1,190).

Probability = Number of students in category / Total number of students
Probability = 160 / 1,190 
Probability = 0.1345 (rounded to 3 decimal places)

Therefore, the best choice is C, which is closest to the calculated probability of 0.135.

Question 12

Given the contingency table shown here,does the decision to retire appear independent of the employee type? Survey question: Do you plan on retiring or keep working when you turn 65? 
A) Yes.
B) No.

Accepted Answer

The answer of Given the contingency table shown here,does the...

Question 13

Given the contingency table shown here,find P(E | F). 
A) .160
B) .300
C) .340
D) .533

Accepted Answer

The answer of Given the contingency table shown here,find P(E...

Question 14

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy and had a college degree? 
A) .0111
B) .0428
C) .0803
D) .2385

Accepted Answer

The answer of Given the contingency table shown here,what is...

Question 15

Given the contingency table shown here,find P(W | M). Survey question: Do you plan on retiring or keep working when you turn 65? 
A) .145
B) .250
C) .581
D) .687

Accepted Answer

To find P(W | M), we need to look at the column for males (M) and find the proportion of those who plan on retiring (W). 
So, P(W | M) = W/M = 121/208 = 0.581. Therefore, the answer is (C).

Question 16

Given the contingency table shown here,what is the probability that a participant selected at random is a graduate student who opposes the change to a quarter system? 
A) .135
B) .250
C) .375
D) .600

Accepted Answer

The answer of Given the contingency table shown here,what is...

Question 17

Given the contingency table shown here,if a mother attended some college but did not have a degree,what is the probability that she did not smoke during her pregnancy? 
A) .2736
B) .8399
C) .8752
D) .9197

Accepted Answer

The answer of Given the contingency table shown here,if a...

Question 18

Given the contingency table shown here,if a randomly chosen student attends a religious school,what is the probability the location is rural? 
A) .142
B) .162
C) .167
D) .333

Accepted Answer

To find the probability of a student attending a religious school in a rural location, we need to look at the column for rural and the row for religious, which has a value of 5. 
The total number of students attending religious schools is 30 (5 + 25), and the total number of students in rural locations is 180 (40 + 140). 
Therefore, the probability is 5/30 or 1/6, which simplifies to approximately 0.167 or 16.7%. 
Therefore, the best choice is C.

Question 19

Given the contingency table shown here,find P(E). 
A) .180
B) .300
C) .529
D) .641

Accepted Answer

The answer of Given the contingency table shown here,find P(E)....

Question 20

Given the contingency table shown here,find P(L or W). Survey question: Do you plan on retiring or keep working when you turn 65? 
A) .750
B) .588
C) .435
D) .895

Accepted Answer

The answer of Given the contingency table shown here,find P(L...

Quiz 5: Probability

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy or that she graduated from college?

Given the contingency table shown here,find P(R ∩ L) . Survey question: Do you plan on retiring or keep working when you turn 65?

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy if her education level was below high school?

Given the contingency table shown here,find the probability that a mother with some college smoked during pregnancy.

Given the contingency table shown here,what is the probability that a mother in the study smoked during pregnancy?

Given the contingency table shown here,if a randomly chosen student attends school in an inner city location,what is the probability that it is a public school?

Ramjac Company wants to set up k independent file servers,each capable of running the company's intranet.Each server has average "uptime" of 98 percent.What must k be to achieve 99.999 percent probability that the intranet will be "up"?

Given the contingency table shown here,if a survey participant is selected at random,what is the probability he/she is an undergrad who favors the change to a quarter system?

Given the contingency table shown here,find the probability that a randomly chosen employee is a line worker who plans to retire at age 65. Survey question: Do you plan on retiring or keep working when you turn 65?

Given the contingency table shown here,if a faculty member is chosen at random,what is the probability he/she opposes the change to a quarter system?

Given the contingency table shown here,what is the probability that a student attends a public school in a rural area?

Given the contingency table shown here,does the decision to retire appear independent of the employee type? Survey question: Do you plan on retiring or keep working when you turn 65?

Given the contingency table shown here,find P(E | F) .

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy and had a college degree?

Given the contingency table shown here,find P(W | M) . Survey question: Do you plan on retiring or keep working when you turn 65?

Given the contingency table shown here,what is the probability that a participant selected at random is a graduate student who opposes the change to a quarter system?

Given the contingency table shown here,if a mother attended some college but did not have a degree,what is the probability that she did not smoke during her pregnancy?

Given the contingency table shown here,if a randomly chosen student attends a religious school,what is the probability the location is rural?

Given the contingency table shown here,find P(E) .

Given the contingency table shown here,find P(L or W) . Survey question: Do you plan on retiring or keep working when you turn 65?