Math Problem Statement

A random experiment produces many possible events. Two of these events are event A and event B. These events are independent of each other and occur with P(A) = 0.4 and P(B) = 0.73. Compute the following probabilities: (a) P(A ∩ B), (b) P(A ∩ B^c), (c) Probability that neither A nor B occurs, (d) Probability that exactly one of these two events will occur.

Solution

Let's work through the problem step by step based on the information given in the image.

We are given:

  • P(A)=0.4P(A) = 0.4
  • P(B)=0.73P(B) = 0.73
  • Events AA and BB are independent.

(a) P(AB)P(A \cap B) (The probability that both AA and BB occur)

Since AA and BB are independent, the probability of their intersection (both occurring) is given by: P(AB)=P(A)×P(B)=0.4×0.73=0.2920P(A \cap B) = P(A) \times P(B) = 0.4 \times 0.73 = 0.2920

(b) P(ABc)P(A \cap B^c) (The probability that AA occurs and BB does not occur)

The complement rule states that P(Bc)=1P(B)P(B^c) = 1 - P(B). Therefore: P(Bc)=10.73=0.27P(B^c) = 1 - 0.73 = 0.27 Now, since AA and BcB^c are also independent: P(ABc)=P(A)×P(Bc)=0.4×0.27=0.1080P(A \cap B^c) = P(A) \times P(B^c) = 0.4 \times 0.27 = 0.1080

(c) Probability that neither AA nor BB will occur

The probability that neither event occurs is given by P(AcBc)P(A^c \cap B^c). Since AA and BB are independent, we can compute: P(Ac)=1P(A)=10.4=0.6P(A^c) = 1 - P(A) = 1 - 0.4 = 0.6 P(AcBc)=P(Ac)×P(Bc)=0.6×0.27=0.1620P(A^c \cap B^c) = P(A^c) \times P(B^c) = 0.6 \times 0.27 = 0.1620

(d) Probability that exactly one of these two events will occur

This is the probability that either AA occurs and BB does not, or BB occurs and AA does not. This can be written as: P(exactly one)=P(ABc)+P(AcB)P(\text{exactly one}) = P(A \cap B^c) + P(A^c \cap B) We already have P(ABc)=0.1080P(A \cap B^c) = 0.1080. Now let's compute P(AcB)P(A^c \cap B): P(AcB)=P(Ac)×P(B)=0.6×0.73=0.4380P(A^c \cap B) = P(A^c) \times P(B) = 0.6 \times 0.73 = 0.4380 Thus: P(exactly one)=0.1080+0.4380=0.5460P(\text{exactly one}) = 0.1080 + 0.4380 = 0.5460

Summary of Results:

  • (a) P(AB)=0.2920P(A \cap B) = 0.2920
  • (b) P(ABc)=0.1080P(A \cap B^c) = 0.1080
  • (c) Probability that neither AA nor BB occurs = 0.16200.1620
  • (d) Probability that exactly one of AA or BB occurs = 0.54600.5460

Would you like more detailed explanations on any of these steps? Let me know if you have any further questions.

Here are 5 follow-up questions to consider:

  1. How would the calculations change if AA and BB were not independent?
  2. Can you explain how to derive the formula for P(AB)P(A \cap B) for dependent events?
  3. How would you compute P(AcBc)P(A^c \cup B^c) instead of their intersection?
  4. What is the relationship between P(AB)P(A \cup B) and P(AB)P(A \cap B)?
  5. How does the complement rule help in solving probability problems?

Tip: Always ensure you check whether events are independent before applying the multiplication rule for their intersection.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Probability
Independent Events
Complement Rule

Formulas

P(A ∩ B) = P(A) × P(B) for independent events
P(B^c) = 1 - P(B)
P(A ∩ B^c) = P(A) × P(B^c) for independent events
P(A^c) = 1 - P(A)
P(A^c ∩ B^c) = P(A^c) × P(B^c) for independent events
P(Exactly one) = P(A ∩ B^c) + P(A^c ∩ B)

Theorems

Multiplication rule for independent events
Complementary rule

Suitable Grade Level

Grades 9-12