Question

At LaGuardia Airport for a certain nightly flight, the probability that it will rain is 0.12 and the probability that the flight will be delayed is 0.08. The probability that it will not rain and the flight will leave on time is 0.82. What is the probability that it is raining if the flight leaves on time? Round your answer to the nearest thousandth.

Answer 1

Answer:

0.109 = 10.9% probability that it is raining if the flight leaves on time.

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

$P(B|A) = \frac{P(A \cap B)}{P(A)}$

In which

P(B|A) is the probability of event B happening, given that A happened.

$P(A \cap B)$ is the probability of both A and B happening.

P(A) is the probability of A happening.

Conditional probability:

Event A: Leaves on time

Event B: Raining

Probability that the flight will be delayed is 0.08.

So 1 - 0.08 = 0.92 probability that it leaves on time, that is, $P(A) = 0.92$

The probability that it will not rain and the flight will leave on time is 0.82.

0.92 - 0.82 = 0.1 probability it is raining and the flight leaves on time, so:

$P(A \cap B) = 0.1$

What is the probability that it is raining if the flight leaves on time?

$P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.1}{0.92} = 0.109$

0.109 = 10.9% probability that it is raining if the flight leaves on time.