Question

In: Statistics and Probability

It is believed that the proportion of female college students who friend-zone a study buddy is...

It is believed that the proportion of female college students who friend-zone a study buddy is about 29%.

  1. a) Say? w?e s?elected? 15 ?random co?llege females?. I?s t?his? s?amp?le ?"lar?ge e???nough"? to us??e ?the Central Limit Theorem? What about 100? Check by using the assumptions for CLT.

  2. b) Fill in the blank to write the sampling distribution when we obtain 100 females. Round to three decimal points if possible. ?̂~? (? , ?)

  3. c) Find the probability that from the 100 females sampled, the sample proportion of friend-zoning a study buddy will be greater than 35%. Round to three decimal points.

Solutions

Expert Solution

a)

given

the proportion of female college students who friend-zone a study buddy is =  0.29 = p

a)

sample size 15 is not large enough to apply central liimit theorem.

to apply CLT we need atleast 30 sample size.

conditons to check assumption -

n*p >= 10 and n*(1-p) >=10

now when n = 15

15 * 0.29 = 4.35 < 10 and 15*(1-0.29) =  10.65 > 10

conditon not met

when n = 100

100 * 0.29 = 29 > 10 and 100 * (1-0.29) = 71 > 10

both conditions met.

b)

the sampling distribution when we obtain 100 females =

c)

We need to compute Pr(p^​≥0.35).

Based on the information provided, the population men of sample proportions and the corresponding standard error are:

Observe that:

np=1000.29=29≥10 , nq=1000.71=71≥10

which indicates that the assumption for normal approximation for the sampling distribution is met.

Now, the following is obtained using normal approximation:

Therefore, based on the information provided, it is concluded that

please like)


Related Solutions

Suppose it is desired to compare the proportion of male and female students who voted in...
Suppose it is desired to compare the proportion of male and female students who voted in the last presidential election. We decide to randomly and independently sample 1000 male and 1000 female students and ask if they voted or not. A printout of the results is shown below. Hypothesis Test - Two Proportions Sample Size Successes Proportion Males 1000 475 0.47500 Females 1000 525 0.52500 Difference -0.05000 Null Hypothesis: p1 = p2 Alternative Hyp: p1 ≠ p2 SE (difference) 0.02236...
A professor states that in the United States the proportion of college students who own iPhones...
A professor states that in the United States the proportion of college students who own iPhones is .66. She then splits the class into two groups: Group 1 with students whose last name begins with A-K and Group 2 with students whose last name begins with L-Z. She then asks each group to count how many in that group own iPhones and to calculate the group proportion of iPhone ownership. For Group 1 the proportion is p1 and for Group...
A professor states that in the United States the proportion of college students who own iPhones...
A professor states that in the United States the proportion of college students who own iPhones is .66. She then splits the class into two groups: Group 1 with students whose last name begins with A-K and Group 2 with students whose last name begins with L-Z. She then asks each group to count how many in that group own iPhones and to calculate the group proportion of iPhone ownership. For Group 1 the proportion is p1 and for Group...
A professor states that in the United States the proportion of college students who own iPhones...
A professor states that in the United States the proportion of college students who own iPhones is .66. She then splits the class into two groups: Group 1 with students whose last name begins with A-K and Group 2 with students whose last name begins with L-Z. She then asks each group to count how many in that group own iPhones and to calculate the group proportion of iPhone ownership. For Group 1 the proportion is p1 and for Group...
A professor states that in the United States the proportion of college students who own iPhones...
A professor states that in the United States the proportion of college students who own iPhones is .66. She then splits the class into two groups: Group 1 with students whose last name begins with A-K and Group 2 with students whose last name begins with L-Z. She then asks each group to count how many in that group own iPhones and to calculate the group proportion of iPhone ownership. For Group 1 the proportion is p1 and for Group...
It has been determined, with 90% confidence, that the proportion of students who graduate from college...
It has been determined, with 90% confidence, that the proportion of students who graduate from college are able to find a job in their field of study lies between 64% and 83%. Using this information answer the following questions. What is the sample proportion? What is the margin of error? Interpret this confidence interval in the context of this problem. ​​​​​​​​​​​​​​What would happen to this interval if the confidence level were to increase to 95%?
10. Suppose the proportion of all college students who have changed their major in the last...
10. Suppose the proportion of all college students who have changed their major in the last two semesters is 60%. If a class of 200 students is considered. What is the probability that the proportion of students who may change their major in the next 2 semesters are more than 115?  
suppose the proportion of all college students who have used marijuana in the past 6months is...
suppose the proportion of all college students who have used marijuana in the past 6months is p=0.40 in a class of 200 students that are representative of all college students would it be unusual for the proportion who have used marijuana in the past 6 months to be less than 0.32? Explain how you made your decision in this question
A random sample with 150 students has 45 female students. Estimate the population proportion of female...
A random sample with 150 students has 45 female students. Estimate the population proportion of female students at the 99% level of confidence. a. Find the right boundary of the estimation? b. Find the margin of error.
A study was being done to estimate the proportion of students who receive financial aid. If...
A study was being done to estimate the proportion of students who receive financial aid. If the study would like to construct 95% confidence interval for the proportion of students receiving financial aid within 3%, what sample size would be needed? A previous study stated that 57% of students receive some form of financial aid.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT