#### MS 150 Statistics Fall 2001 Quiz 05

Forty-two students were asked whether, when they are sick, they prefer to be left alone to have some one care for them. The results are tabulated below.  Note that 21 male students indicated they prefer to be left alone, ten male students indicated they prefer to be cared for, nine female students said they prefer to be left alone, and ten female students prefer to be cared for.

 Left alone (L) Cared for (C) Male (M) 21 10 _____ Female (F) 9 10 _____ _____ _____ _____
1. Find the probability that a student in the forty-two wants to be left alone:

P(L) = _____

2. Find the complement of the above:  P(Not L) = _____

3. Find the probability that a student in the forty-two wants is female:

P(F) = _____

4. Find the probability that a student in the forty-two wants is male AND wants to be left alone :

P(M and L) = _____

5. Find the probability that a student in the forty-two wants is female AND wants to be left alone :

P(F and L) = _____

6. According to the data above, do men or women more frequently want to be left alone when sick?

7. Find the probability that a student in the forty-two wants is female OR wants to be left alone:

P(F or L) = _____

8. Find the probability that a student in the forty-two is female given that the student wants to be cared for:

P(F, given C) = _____

9. Find the probability that a student in the forty-two wants to be left alone given that the student is female:

P(L, given F) = _____