Author: Anonymous

A population has μ = 120, σ = 20. For n = 64, find P(117 < x̄ < 124).

A normally distributed variable has mean μ = 82 and standard deviation σ = 10. Find P(X < 75.0).

The population proportion is p = 0.40. For a random sample of n = 100, find P(p̂ < 0.45).

A population has standard deviation σ = 18. For samples of size n = 81, find the standard deviation of the sampling distribution of x̄.

X is normally distributed with μ = 50 and σ = 5. Find P(X > 57.0).

A normally distributed variable has mean μ = 70 and standard deviation σ = 8. Find P(X < 80.0).

The population proportion is p = 0.50. For n = 100, find P(0.45 < p̂ < 0.58).

For x̄ = 100, s = 14, n = 36, find the margin of error for a 90% confidence interval for μ (σ unknown).

A population has μ = 50, σ = 10. For n = 100, find P(49 < x̄ < 52).

For x̄ = 90, s = 12, n = 30, find the margin of error for a 95% confidence interval for μ (σ unknown).