HLTH 335 Lab 2 (University of Notre Dame)

HLTH 335. Section 103 Lab 2

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Be sure to support your solutions with the supporting SAS code, where appropriate.

Question (not from textbook)
A and B are mutually exclusive events. P(A) = 0.3; P(B) = 0.6. Find
a. P(A and B) =
b. P(A∣B) =
c. P(A or B) =

Answer:

a. P(A and B) = P(A|B) * P(B) = 0.54
b. A and B are not mutually exclusive since P(A and B) is not equal to 0
c. A and B are not independent since P(B|A) does not equal P(A).
d. P (A or B) = 0.36
e. P(B|A) = 1.8

Not possible for probability to be 180%.



Supporting SAS Code:

/*Q1*/

DATA prob;
INPUT p_A p_B p_AgivenB;

/* part a */
p_AandB = p_AgivenB *p_B;

/* part d */
p_AorB = p_A + p_B - p_AandB;

/* part e */
p_BgivenA = p_AandB / p_A;

CARDS;
0.3 0.6 0.9
;
RUN;
PROC PRINT DATA=prob;
RUN;

, HLTH 335. Section 103 Lab 2

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Question (not from textbook)
C and D are mutually exclusive events. P(C) = 0.1; P(D) = 0.1. Find
a. P(C and D) =
b. P(C∣D) =
c. P(C or D) =

Answer:

Insert your answer here




Supporting SAS Code:

Insert your SAS code here




Question (not from textbook)
A and B are independent events. P(A|B) = 0.5. Find P(A).

Answer:

Insert your answer here




Supporting SAS Code:

Insert your SAS code here




Question (not from textbook)
C and D are independent events. P(C|D) = 0.9. Find P(C).