Math Problem Statement

Given the probability distributions shown to the​ right, complete the following parts. a. Compute the expected value for each distribution. b. Compute the standard deviation for each distribution. c. What is the probability that x will be at least 3 in Distribution A and Distribution​ B? d. Compare the results of distributions A and B. Distribution A Distribution B

x Subscript i ​P(Xequalsx Subscript i​) x Subscript i ​P(Xequalsx Subscript i​) 0 0.06 0 0.40 1 0.12 1 0.25 2 0.17 2 0.17 3 0.25 3 0.12 4 0.40 4 0.06 Question content area bottom Part 1 a. What is the expected value for distribution​ A? muequals    enter your response here ​(Type an integer or decimal rounded to three decimal places as​ needed.)

Solution

Let's start by calculating the expected value (mean) for Distribution A. The formula for the expected value is:

μ=(xiP(X=xi))\mu = \sum (x_i \cdot P(X = x_i))

For Distribution A, the values for xix_i and P(X=xi)P(X = x_i) are as follows:

xix_iP(X=xi)P(X = x_i)
00.06
10.12
20.17
30.25
40.40

Now we calculate the expected value for Distribution A:

μA=(00.06)+(10.12)+(20.17)+(30.25)+(40.40)\mu_A = (0 \cdot 0.06) + (1 \cdot 0.12) + (2 \cdot 0.17) + (3 \cdot 0.25) + (4 \cdot 0.40)

Let's compute this:

μA=(0)+(0.12)+(0.34)+(0.75)+(1.60)=2.81\mu_A = (0) + (0.12) + (0.34) + (0.75) + (1.60) = 2.81

So, the expected value for Distribution A is:

μA=2.81\mu_A = 2.81


Now, let's calculate the expected value for Distribution B using the same formula:

xix_iP(X=xi)P(X = x_i)
00.40
10.25
20.17
30.12
40.06

μB=(00.40)+(10.25)+(20.17)+(30.12)+(40.06)\mu_B = (0 \cdot 0.40) + (1 \cdot 0.25) + (2 \cdot 0.17) + (3 \cdot 0.12) + (4 \cdot 0.06)

Let's compute this:

μB=(0)+(0.25)+(0.34)+(0.36)+(0.24)=1.19\mu_B = (0) + (0.25) + (0.34) + (0.36) + (0.24) = 1.19

So, the expected value for Distribution B is:

μB=1.19\mu_B = 1.19


Answers:

  • a. Expected value for Distribution A: μA=2.81\mu_A = 2.81
  • b. Expected value for Distribution B: μB=1.19\mu_B = 1.19

Do you want me to proceed with the standard deviation, or do you have any questions so far?

Here are five related questions that expand on this information:

  1. How is the variance related to the standard deviation in a probability distribution?
  2. How can expected values be interpreted in real-life contexts?
  3. What happens to the expected value if all probabilities are equal?
  4. What is the significance of a higher expected value in a probability distribution?
  5. How do you compute the expected value for a continuous distribution?

Tip: The expected value is often referred to as the long-run average or mean when considering repeated trials of a probability experiment.

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Math Problem Analysis

Mathematical Concepts

Probability Distributions
Expected Value
Standard Deviation

Formulas

Expected value formula: E(X) = Σ [x_i * P(X = x_i)]
Standard deviation formula: σ = sqrt(Σ [(x_i - μ)^2 * P(X = x_i)])
Probability formula: P(X ≥ x)

Theorems

Law of Large Numbers (related to expected value)
Properties of Discrete Probability Distributions

Suitable Grade Level

Grades 10-12