Math Problem Statement

p(a) = 1/9, p(b) = 1/3, p(a|b) = 1/2 independent or dependent

Solution

To determine whether the events AA and BB are independent or dependent, we check if they satisfy the condition for independence:

P(AB)=P(A)P(A|B) = P(A)

If the conditional probability P(AB)P(A|B) is equal to the probability P(A)P(A), then the events are independent. Otherwise, they are dependent.

Given:

  • P(A)=19P(A) = \frac{1}{9}
  • P(B)=13P(B) = \frac{1}{3}
  • P(AB)=12P(A|B) = \frac{1}{2}

Now, let's calculate the product P(A)×P(B)P(A) \times P(B) and compare it to P(AB)×P(B)P(A|B) \times P(B).

If P(A)×P(B)=P(AB)P(A) \times P(B) = P(A \cap B), then the events are independent.

P(AB)=P(AB)×P(B)=12×13=16P(A \cap B) = P(A|B) \times P(B) = \frac{1}{2} \times \frac{1}{3} = \frac{1}{6}

Now, compare P(AB)P(A \cap B) with P(A)×P(B)P(A) \times P(B):

P(A)×P(B)=19×13=127P(A) \times P(B) = \frac{1}{9} \times \frac{1}{3} = \frac{1}{27}

Since P(AB)=16127P(A \cap B) = \frac{1}{6} \neq \frac{1}{27}, the events AA and BB are dependent.


Would you like further details or have any questions?

Here are 5 related questions:

  1. What is the definition of conditional probability?
  2. How do we compute the joint probability of two events?
  3. What is the difference between mutually exclusive and independent events?
  4. How can we use a Venn diagram to illustrate dependent events?
  5. How do dependent events affect the calculation of probabilities in a sequence of trials?

Tip: When events are dependent, the occurrence of one event changes the likelihood of the other event happening.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Probability Theory
Conditional Probability
Independence and Dependence of Events

Formulas

P(A|B) = P(A ∩ B) / P(B)
P(A ∩ B) = P(A|B) × P(B)
P(A) × P(B) for independent events

Theorems

Independence Rule for Events

Suitable Grade Level

Grades 10-12