Question

In: Statistics and Probability

In a recent survey about US policy in Iraq, 62 % of the respondents said that...

  1. In a recent survey about US policy in Iraq, 62 % of the respondents said that they support US policy in Iraq. Females comprised 53% of the sample, and of the females, 46% supported US policy in Iraq. A person is selected at random.
  1. What is the probability that the person we select is female and supports U.S. policy in Iraq?
  2. Are the events "does not support U.S, policy in Iraq" and "female" statistically independent? Why or why not?
  3. What is the probability that the person we select is male?
  4. What is the probability that the person we select does not support US policy in Iraq?
  5. What is the probability that the person we select is female and does not support US policy in Iraq?
  6. What is the probability that the person we select is male and does support US policy in Iraq?
  7. What is the probability that the person we select is male and does not support US policy in Iraq?
  8. Suppose we select a supporter of US policy in Iraq, what is the probability that the person we select is female?
  9. ) Suppose we select a person who does not support US policy in Iraq, what is the probability that the person is male?

Solutions

Expert Solution

a) What is the probability that the person we select is female and support US policy in Iraq?

ans:Event S: Support US policy in Iraq, E vent F:Female

F(S) = 0.62, P(F) =0.53 and P(S|F) = 0.46

therefore,

P(F∩S) = P(S| F)*P(F) = (0.46)(0.53) = 0.2438

b)Are the events “does not support US policy in Iraq” and “female” statistically independent? Why or why not?

ans: P(F| S) = P(FS) / P(S) = 0.2862 / 0.38 = 0.753 and P(F) = 0.53

Since P(F| S) *P(F), the events “ does not support US policy in Iraq” and “female” are not statistically independent.

c) What is the probability that the person we select is male?

ans:Event M: Male

P(M) = 1 – P(F) = 1 – 053 = 0.47

d) What is the probability that the person we select does not support US policy in Iraq?

ans:

US Policy in Iraq

Support Doesn't Support Row Total
Female 0.2438 0.2862 0.53
Male 0.3762 0.0938 0.47
Column Total 0.62 0.38 1.00

e) What is the probability that the person we select is female and doe not support US policy in Iraq?

ans:P(F) = P(F I S) + P(F I S)*0.53 = 0.2438 + P(F I S).

Hence, P(F I S) = 0.2862.

f)What is the probability that the person we select is male and supports US policy in Iraq?

ans: P(S) = P(S I F) + P(S I M) *0.62 = 0.2438 + P(S I M).

Hence, P(S I M) = 0.3762

g)What is the probability that the person we select is male and does not support US policy in Iraq?

ans: P(M) = P(M I S) + P(M I S)*0.47 = 0.3762 + P(M I S).

Hence, P(M I S) = 0.0938.

h) Suppose we select a supporter of US policy in Iraq, what is the probability that the person we select is female?

ans: P(F | S) = P(F I S) / P(S) = 0.2438 / 0.62 = 0.393

i) Suppose we select a person who does not support US policy in Iraq, what is the probability that the person is male?

ans: P(M | S) = P(M I S) / P(S) = 0.0938 / 0.38 = 0.247


Related Solutions

In a recent survey about appliance ownership, 58.3% of the respondents indicated that they own Maytag...
In a recent survey about appliance ownership, 58.3% of the respondents indicated that they own Maytag appliances, while 23.9% indicated they own both Maytag and GE appliances and 70.7% said they own at least one of the two appliances. Define the events as: M = Owning a Maytag appliance G = Owning a GE appliance [1] What is the probability that a respondent owns a GE appliance? [1] Given that a respondent owns a Maytag appliance, what is the probability...
In a USA Today survey, 20.8% of 144 respondents said that they aspire to have their...
In a USA Today survey, 20.8% of 144 respondents said that they aspire to have their boss’s job. Construct a 95% confidence interval estimate of all workers who aspire to have their boss’s job by completing the following questions. (Triola, 2014) Identify the following: = ______ (0.5 points) = ______ (0.5 points) Draw the standard normal curve graph for the 95% confidence interval (1 point). Calculate the zα/2 and include it in the graph (1 point for listing the zα/2,...
In a poll conducted by the General Social Survey, 79% of respondents said that their jobs...
In a poll conducted by the General Social Survey, 79% of respondents said that their jobs were sometimes or always stressful. Two hundred workers are chosen at random. Use the TI-84 Plus calculator as needed. Round your answer to at least four decimal places. (a) Approximate the probability that 165 or fewer workers find their jobs stressful. (b) Approximate the probability that more than 158 workers find their jobs stressful. (c) Approximate the probability that the number of workers who...
Suppose a survey revealed that 20% of 481 respondents said they had in the past sold...
Suppose a survey revealed that 20% of 481 respondents said they had in the past sold unwanted gifts over the Internet. (a) Use the information to construct a 90% confidence interval for the population proportion who sold unwanted gifts over the Internet, rounding your margin of error to the nearest hundredth. (Round your answers to two decimal places.) ( , ) (b) Use the information to construct a 98% confidence interval for the population proportion who sold unwanted gifts over...
Suppose a survey revealed that 22% of 502 respondents said they had in the past sold...
Suppose a survey revealed that 22% of 502 respondents said they had in the past sold unwanted gifts over the Internet. (a) Use the information to construct a 90% confidence interval for the population proportion who sold unwanted gifts over the Internet, rounding your margin of error to the nearest hundredth. (Round your answers to two decimal places.) (  ,  ) (b) Use the information to construct a 98% confidence interval for the population proportion who sold unwanted gifts over the Internet,...
Suppose a survey revealed that 19% of 494 respondents said they had in the past sold...
Suppose a survey revealed that 19% of 494 respondents said they had in the past sold unwanted gifts over the Internet. (a) Use the information to construct a 90% confidence interval for the population proportion who sold unwanted gifts over the Internet, rounding your margin of error to the nearest hundredth. (Round your answers to two decimal places.) (_________ , __________ ) (b) Use the information to construct a 98% confidence interval for the population proportion who sold unwanted gifts...
A survey of US women with Ph.D.'s was conducted. Of the 102 respondents in marriages or...
A survey of US women with Ph.D.'s was conducted. Of the 102 respondents in marriages or long-term partnerships with men, 57% reported that their spouse/partner also held a doctorate degree. Construct a theoretical 90% confidence interval. The interval is: Select one: a. (49.0%, 64.7%) b. (48.9%, 65.1%) c. (47.1%, 66.7%) d. (47.4%, 66.6%) e. (44.4%, 69.6%) Based on the interval in the previous question, what group(s) can we make a conclusion about? Select one: a. All US women b. All...
A research group conducted a survey about church attendance. The survey respondents were asked about their...
A research group conducted a survey about church attendance. The survey respondents were asked about their church attendance and asked to indicate their age. The results are as follows: Church Attendance Age 20 to 29 30 to 39 40 to 49 50 to 59 Yes 60 30 68 100 No 87 107 80 50 Answer the following four questions. Use 5% level of significance throughout. 1.We use the sample data above to determine whether church attendance is independent of age....
(a) According to Graduating Student and Alumni Survey in 2019, among the 1230 respondents, 180 said...
(a) According to Graduating Student and Alumni Survey in 2019, among the 1230 respondents, 180 said that they expected difficulty finding a job after graduation. If we can reasonably presume that the percentage of people expected difficulty will be between 15% and 25%, obtain a sample size that will ensure a margin of error of at most 0.02 for a 90% confidence interval. (b) A recent survey of 254 customers, selected at random from a database with 12,861 customers, found...
A recent survey by the New Statesman on British social attitudes asked respondents if they believe...
A recent survey by the New Statesman on British social attitudes asked respondents if they believe that inequality is too large. The survey found that 68% of the respondents do believe inequality is too large. In a sample of six British citizens, what is the probability that two believe inequality is too large? If required, round your answer to four decimal places. f (2) = In a sample of six British citizens, what is the probability that at least two...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT