Question 309465: In a large university, 20% of the students are business majors. A random sample of 100 students is selected, and their majors are recorded.
a. compute the standard error of the proportion.
b. what is the probability that the sample contains at least 12 business majors?
c. what is the probability that the sample contains less than 15 business majors?
d. what is the probability that the sample contains between 12 and 14 business majors?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! In a large university, 20% of the students are business majors. A random sample of 100 students is selected, and their majors are recorded.
---
a. compute the standard error of the proportion.
Ans: sqrt[pq/n] = sqrt[0.2*0.8/100]
------------------------------------------
b. what is the probability that the sample contains at least 12 business majors?
Ans: Binomial Problem with n = 100 ; p = 0.2 ; 12<= x <=100
Ans: 1-binomcdf(100,0.2,11) = 0.9874
------------------------------------------
c. what is the probability that the sample contains less than 15 business majors?
Ans: binomcdf(100,0.2,14) = 0.0804
------------------------------------------
d. what is the probability that the sample contains between 12 and 14 business majors?
Ans: binomcdf(100,0.2,14)-binomcdf(100,0.2,11) = 0.0679
==============================================================
Cheers,
Stan H.
=====================
|
|
|
