Questions: You are given the following information about the events A, B, and C.
- P(A)=0.55
- P(B)=0.45
- P(C)=0.40
- P(A and B)=0.2475
- P(B and C)=0.1644
- P(A and C)=0.2034
Determine which (if any) pairs of the three events are independent.
Transcript text: You are given the following information about the events $A, B$, and $C$.
- $P(A)=0.55$
- $P(B)=0.45$
- $P(C)=0.40$
- $P(A$ and $B)=0.2475$
- $P(B$ and $C)=0.1644$
- $\mathrm{P}(\mathrm{A}$ and C$)=0.2034$
Determine which (if any) pairs of the three events are independent.
Solution
Solution Steps
To determine if pairs of events are independent, we need to check if the probability of the intersection of two events equals the product of their individual probabilities. Specifically, for events \(A\) and \(B\) to be independent, \(P(A \cap B) = P(A) \cdot P(B)\). We will perform similar checks for the pairs \( (A, C) \) and \( (B, C) \).
Step 1: Check Independence of Events \(A\) and \(B\)
To determine if events \(A\) and \(B\) are independent, we check the condition:
\[
P(A \cap B) = P(A) \cdot P(B)
\]
Calculating the right side:
\[
P(A) \cdot P(B) = 0.55 \cdot 0.45 = 0.2475
\]
Since \(P(A \cap B) = 0.2475\), we find that:
\[
P(A \cap B) = P(A) \cdot P(B) \implies \text{Events } A \text{ and } B \text{ are not independent.}
\]
Step 2: Check Independence of Events \(B\) and \(C\)
Next, we check if events \(B\) and \(C\) are independent:
\[
P(B \cap C) = P(B) \cdot P(C)
\]
Calculating the right side:
\[
P(B) \cdot P(C) = 0.45 \cdot 0.40 = 0.18
\]
Since \(P(B \cap C) = 0.1644\), we find that:
\[
P(B \cap C) \neq P(B) \cdot P(C) \implies \text{Events } B \text{ and } C \text{ are not independent.}
\]
Step 3: Check Independence of Events \(A\) and \(C\)
Finally, we check if events \(A\) and \(C\) are independent:
\[
P(A \cap C) = P(A) \cdot P(C)
\]
Calculating the right side:
\[
P(A) \cdot P(C) = 0.55 \cdot 0.40 = 0.22
\]
Since \(P(A \cap C) = 0.2034\), we find that:
\[
P(A \cap C) \neq P(A) \cdot P(C) \implies \text{Events } A \text{ and } C \text{ are not independent.}
\]
Final Answer
No pairs of events are independent. Thus, the answer is:
\[
\boxed{\text{No pairs of events are independent.}}
\]