This preview shows pages 1–3. Sign up to view the full content.

Practice Questions 2 Answers 1. a. C b. A 2. C 3. a. P (A) = 0.17 + 0.13 + 0.04 = 0.34 b. No, since P ( A U B ) S . c. P ( A ) =1 – P( A ) = 1 – 0.34 = 0.66 d. P ( A I B ) = 0, since A and B are mutually exclusive events. 4. a. Event S: Supports US policy in Iraq, Event F: Female. P ( S ) = 0.62, P ( F ) = 0.53 and P ( S | F ) = 0.46. Therefore, P ( F I S ) = P ( S | F ) P ( F ) = (0.46)(0.53) = 0.2438 b. P ( F | S ) = P ( F S I ) / P ( S ) = 0.2862 / 0.38 = 0.753 and P ( F ) = 0.53 Since P ( F | S ) P ( F ), the events “ does not support US policy in Iraq” and “female” are not statistically independent. c. Event M: Male P ( M ) = 1 – P ( F ) = 1 – 053 = 0.47 d. ANSWER: P (Does not support US policy in Iraq) = 1 – P ( S ) = 1 – 0.62 = 0.38 US Policy in Iraq Gender e. P ( F ) = P ( F I S ) + P ( F S I ) 0.53 = 0.2438 + P ( F S I ). Hence, P ( F S I ) = 0.2862. f. P ( S ) = P ( S I F ) + P ( S I M ) 0.62 = 0.2438 + P ( S I M ). Hence, P ( S I M ) = 0.3762. g. P ( M ) = P ( M I S ) + P ( M I S ) 0.47 = 0.3762 + P ( M I S ). Hence, P ( M I S ) = 0.0938. Support Doesn’t Support Row Total Female 0.2438 0.2862 0.53 Male 0.3762 0.0938 0.47 Column Total 0.62 0.38 1.00

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
h. P ( F | S ) = P ( F I S ) / P ( S ) = 0.2438 / 0.62 = 0.393
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}