Of the 8 members of teacher in school, 5 can teach Physics, 7 can teach Math, and 4 can teach both subject. If one member is chosen at random, what is the probability that the member chosen will be someone who can not teach either subject? Choose the correct choice from the following answers.
A) a) 5/18
B) b) 7/18
C) c) 1/2
D) d) 0
E) e) 13/18
You know how to solve for Total number of people who can teach at least one subject:   Total = n(A) + n(B) - n(A and B)   Total people who can teach at least one subject = 5 + 7- 4= 
<gadget id="calculator">5 + 7- 4</gadget>
<output>8</output>
8   So 8 people know how to teach at least one subject. Hence, if you pick anyone, the probability is 0 that he/she wouldn't know how to teach any subject.   Answer (d) 0)
<result>D</result>
Of the 8 members of teacher in school, 5 can teach Physics, 7 can teach Math, and 4 can teach both subject. If one member is chosen at random, what is the probability that the member chosen will be someone who can not teach either subject?