Question

1. One stats class consists of 52 women and 28 men.  Assume the average exam score on Exam 1 was 74 (σ = 10.43; assume the whole class is a population).

   Using random sampling, what is the probability that the first exam I select from a stack will be a male student?

QUESTION 6

1. One stats class consists of 52 women and 28 men.  Assume the average exam score on Exam 1 was 74 (σ = 10.43; assume the whole class is a population).

   If I select two exams and those are both male students, what is the probability that the third exam I select will be that of a female student?

Answer 1

No. of male students = 28

No. of female students = 52

Total number of students = 28 + 52 = 80

In random sampling, individual is chosen randomly and entirely by chance, such that each individual has the same probability of being chosen at any stage during the sampling process

Probability that the first exam I select from a stack will be a male student = 28/80 = 0.35

If the first two exams selected are both male students, the number of exams of male students left is 26 and the number of exams of female students left is 52

Thus, probability that the third exam will be that of a female student

= # of female students/Total # of students

= 52/(52 + 26) = 2/3