Question

University degree requirements typically are different for Bachelor of Science degrees and Bachelor of Arts degrees. Some students get a Bachelor of Arts and Science degree, which requires meeting graduation criteria for both degrees. A student advisor needs to know the probability a newly admitted student is interested in such a program, so that the student can be properly advised. A study of previous years finds that the probability a student gets a Bachelor of Science degree is P(Science)=0.3 and the probability a student gets a Bachelor of Arts degree is P(Arts)=0.6 . The study also shows that the probability a student gets no degree is P(no)=0.2 .

A - The probability a student gets a Bachelor of Arts and Science degree is:
a) 0.3.
b) 0.6.
c) 0.1.
d) 0.2.
B - The probability a student gets a Bachelor of Arts degree or a Bachelor of Science degree is:
a) 0.9.
b) 0.3.
c) 0.6.
d) 0.8.
C - The probability a student gets only a Bachelor of Arts degree is:
a) 0.1.
b) 0.5.
c) 0.3.
d) 0.6.
D - The probability a student gets a Bachelor of Arts and Science degree is:
a) 0.5.
b) 0.1.
c) 0.3.
d) 0.2.
E - If getting a Bachelor of Science degree is independent of getting a Bachelor of Arts degree, the probability of getting a Bachelor of Arts and Science degree is:
a) None of the answer options are correct.
b) 0.18.
c) 0.1.
d) 0.2.

Answer 1

(A) c) 0.1

(B) a) 0.9

(C) b) 0.5

(D) b) 0.1

(E) b) 0.18

Explanation:

Given;

P(science) = 0.3

P(Arts) = 0.6

P(no degree) = 0.2

(A) The probability a student gets a Bachelor of Arts and Science degree;

= 1 - [P(science) + P(Arts)]

= 1 - (0.6 + 0.3)

= 1 - 0.9

= 0.1

(B) The probability a student gets a Bachelor of Arts degree or a Bachelor of Science degree is

= P(Science) + P(Arts)

= 0.3 + 0.6

= 0.9

(C) The probability a student gets only a Bachelor of Arts degree is

= P(Arts ) - P(Science and Arts)

= 0.6 - 0.1

= 0.5

(D) The probability a student gets a Bachelor of Arts and Science degree is:

1 - [P(science) + P(Arts)]

= 1 - (0.6 + 0.3)

= 1 - 0.9

= 0.1

(E) Independent case

= P(Science) and P(Arts)

= 0.3 x 0.6

= 0.18