Questions: By rewriting the formula for the Multiplication Rule, you can write a formula for finding conditional probabilities. The conditional probability of event B occurring, given that event A has occurred, is P(B A) = P(A and B) / P(A). Use the information below to find the probability that a flight arrives on time given that it departed on time.
The probability that an airplane flight departs on time is 0.92. The probability that a flight arrives on time is 0.87. The probability that a flight departs and arrives on time is 0.81.
The probability that a flight arrives on time given that it departed on time is (Round to the nearest thousandth as needed.)
Transcript text: By rewriting the formula for the Multiplication Rule, you can write a formula for finding conditional probabilities. The conditional probability of event $B$ occurring, given that event $A$ has occurred, is $P(B \mid A)=\frac{P(A \text { and } B)}{P(A)}$. Use the information below to find the probability that a flight arrives on time given that it departed on time.
The probability that an airplane flight departs on time is 0.92 .
The probability that a flight arrives on time is 0.87 .
The probability that a flight departs and arrives on time is 0.81 .
The probability that a flight arrives on time given that it departed on time is (Round to the nearest thousandth as needed.)
Solution
Solution Steps
Step 1: Define the Given Probabilities
We are given the following probabilities:
\( P(A) = P(\text{depart on time}) = 0.92 \)
\( P(B) = P(\text{arrive on time}) = 0.87 \)
\( P(A \text{ and } B) = P(\text{depart and arrive on time}) = 0.81 \)
Step 2: Apply the Conditional Probability Formula
To find the conditional probability \( P(B \mid A) \), we use the formula:
\[
P(B \mid A) = \frac{P(A \text{ and } B)}{P(A)}
\]
Substituting the known values:
\[
P(B \mid A) = \frac{0.81}{0.92}
\]
Step 3: Calculate the Conditional Probability
Calculating the above expression:
\[
P(B \mid A) \approx 0.8804347826086957
\]
Rounding this value to the nearest thousandth gives:
\[
P(B \mid A) \approx 0.8804
\]
Final Answer
The probability that a flight arrives on time given that it departed on time is \\(\boxed{0.880}\\).