In a nationwide poll, N people were interviewed. If 1/4 of them answered "yes" to question 1, and of those, 1/3 answered "yes" to question 2, whih of the following expressions represents the number of people interviewed who did NOT answer "yes" to both questions?
N respondents would have fallen under one of 4 possible categories:
Q1 - Y, Q2 - N
Q1 - Y, Q2 - Y
- > information provided
Q1 - N, Q2 - N
Q1 - N, Q2 - Y
With the information provided, we can formulate the Q1 and Q2 - Y repondents = (1/3) x (1/x4) x N. = (1/12)xN ......Since Q1- Yes Respondents = (1/4)xN.
The questions is asking for the number that DID NOT answer yes to both questions, which refer to the other 3 combination possilbillities as shown above.
Therfore the answer = N - (no. of those of answered yes to both)
= N - (1/12)N