Use bayes theorem to solve this problem, a paper bag contains two red balls and one blue ball. A plastic bag contains three blue balls and one red ball. A coin is tossed. If it falls heads up, the paper bag is selected and a ball is drawn. If the coin falls tails up, the plastic bag is selected and a ball is drawn. If a red ball is selected what is the probability that it came from the paper bag?

Respuesta :

Answer:[tex]\frac{8}{11}[/tex]

Step-by-step explanation:

Given

Probability of selecting Paper bag is equivalent to getting a head in coin i.e. 0.5 and probability of selecting Plastic bag is equivalent to getting a tail in coin i.e. 0.5

Probability of getting a red ball from Paper bag[tex]=\frac{2}{3}[/tex]

Probability of getting a red ball from Plastic bag[tex]=\frac{1}{4}[/tex]

If a red ball is selected Probability that it came from the paper bag

[tex]P=P(Red\ ball\ from\ paper\ bag|Red\ ball)[/tex]

[tex]P=\frac{\frac{1}{2}\times \frac{2}{3}}{\frac{1}{2}\times \frac{2}{3}+\frac{1}{2}\times \frac{1}{4}}[/tex]

[tex]P=\frac{2}{2+\frac{3}{4}}=\frac{8}{11}[/tex]

If a red ball is selected, the probability that it came from the paper bag is; ⁸/₁₁

How to use Baye's theorem for conditional Probability?

When tossing a coin, the probability of getting a head is equal to the probability of getting a tail which is 0.5.

Now, since the probability of selecting paper bag is equal to getting a head and probability of selecting Plastic bag is equal to getting a tail, then;

Probability of getting a red ball from Paper bag = 2/3

Probability of getting a red ball from Plastic bag = 1/4

Thus, using Baye's  theorem, If a red ball is selected, the probability that it came from the paper bag is;

P(Red ball from paper bag|Red ball) = (¹/₂ * ²/₃)/((¹/₂ * ²/₃) + (¹/₂ * ¹/₄))

P(Red ball from paper bag|Red ball) = ⁸/₁₁

Read more about Baye's theorem at; https://brainly.com/question/16038936

Q&A Education