Math Problem Statement

The National Coffee Association reported that 63% of U.S. adults drink coffee daily. A random sample of 250 U.S. adults is selected. Round your answers to at least four decimal places as needed.

Solution

To address questions related to this scenario, it's essential to understand that this falls under the concept of binomial probability, given that the outcome for each individual adult is either "drinks coffee" or "does not drink coffee."

  1. Binomial Distribution Characteristics:

    • Number of trials, n=250n = 250.
    • Probability of success (an individual drinks coffee), p=0.63p = 0.63.
    • Probability of failure (an individual does not drink coffee), q=1p=0.37q = 1 - p = 0.37.
  2. Questions You Might Explore:

    a. Probability of Exactly kk Coffee Drinkers in the Sample: To find the probability that exactly kk U.S. adults in the sample drink coffee, use the binomial probability formula: P(X=k)=(nk)pk(1p)nkP(X = k) = \binom{n}{k} p^k (1-p)^{n-k} where (nk)\binom{n}{k} is the binomial coefficient, calculated as: (nk)=n!k!(nk)!\binom{n}{k} = \frac{n!}{k!(n-k)!}

    b. Expected Value and Standard Deviation:

    • The expected number E(X)E(X) of coffee drinkers: E(X)=np=250×0.63=157.5E(X) = np = 250 \times 0.63 = 157.5

    • The standard deviation σ\sigma of the distribution: σ=np(1p)=250×0.63×0.377.6494\sigma = \sqrt{np(1-p)} = \sqrt{250 \times 0.63 \times 0.37} \approx 7.6494

  3. Normal Approximation: When nn is large, a binomial distribution can be approximated by a normal distribution with mean μ=np\mu = np and standard deviation σ=np(1p)\sigma = \sqrt{np(1-p)}.

    • Use continuity correction if using the normal approximation to find probabilities.

For specific probability calculations, you would need to plug in the appropriate values of kk to use the binomial or normal approximation formulas. If you have specific probability questions in mind, feel free to ask!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Binomial Probability
Expected Value
Standard Deviation
Normal Approximation

Formulas

P(X = k) = \binom{n}{k} p^k (1-p)^{n-k}
E(X) = np
σ = \sqrt{np(1-p)}

Theorems

Binomial Theorem
Normal Approximation to Binomial

Suitable Grade Level

Grades 10-12