Question

If the probability of getting Rh+ve is 0.9 and probability of new born being male is \(1/2\), then the probability of new born being male with Rh+ve is

• A. 0.95
• B. 0.45
• C. 0.50
• D. 0.25

Hint:

For independent events: \[ P(A\cap B)=P(A)P(B) \]

Answer 1

The Correct Option is B

Concept: For independent events: \[ P(A\cap B)=P(A)\times P(B) \]

Step 1: Identify probabilities.
\[ P(\text{Rh+ve})=0.9 \] \[ P(\text{Male})=\frac12 \]

Step 2: Find joint probability.
\[ P(\text{Male and Rh+ve}) = 0.9\times \frac12 \] \[ = 0.45 \] \[ \boxed{0.45} \] Hence, \[ \boxed{\text{Option (B)}} \]