Suppose that it snows in Greenland an average of once every 27 days, and when it does, glaciers have a 26% chance of growing. When it does not snow in Greenland, glaciers have only a 4% chance of growing. What is the probability that it is snowing in Greenland when glaciers are growing? (Round your answer to four decimal places.)

Respuesta :

Answer:

0.1998

Step-by-step explanation:

This is a conditional probability question.

We solve this question using Bayes's Theorem of conditional probability.

P(A|B) = [P(B|A) × P(A)] ÷ [(P(B|A) × P(A))+ (P(B|A') × P(A'))]

Based on the information in the question, we have the following values.

Suppose it snows in Greenland once every 27 days.

Probability (it snows) = P(A) = 1/27

= 0.037037037

Approximately = 0.0370

Probability ( it doesn't snow) = P(A') = 1 - 0.0370 = 0.963

Probability ( that when it snow, glaciers grow) = P(B|A) = 26% = 0.26

Probability( that is doesn't snow , glaciers grow) = P(B|A)' = 4% = 0.04

Using the Bayes's Theorem of conditional probability

Probability that it is snowing in Greenland when glaciers are growing is =

P(A|B) = [P(B|A) × P(A)] ÷ [(P(B|A) × P(A))+ (P(B|A') × P(A'))]

= [0.26 × 0.0370] ÷ [(0.26 × 0.0370) + (0.04 × 0.963)]

= 0.00962 ÷( 0.00962 + 0.03852)

=0.00962 ÷ 0.04814

= 0.199833818

Approximately to 4 decimal places ≈ 0.1998

Therefore, probability that it is snowing in Greenland when glaciers are growing is 0.1998