Construct a 95% confidence interval for the population mean, $\mu.$ Assume the population has a normal distribution. A sample of 25 randomly selected students has a mean test score of 81.5 with a standard deviation
Of 10.2.
A)(77.29, 85.71)
B)(56.12, 78.34)
C)(66.35, 69.89)
D)(87.12, 98.32)

Question

Quizplus · Accepted Answer

The 95% confidence interval for the mean can be calculated using the formula: $\bar{x} \pm z \frac{\sigma}{\sqrt{n}}$, where $\bar{x}$ is the sample mean, $z$ is the z-score corresponding to the confidence level (for 95%, $z = 1.96$), $\sigma$ is the standard deviation, and $n$ is the sample size. Plugging in the given values: $81.5 \pm 1.96 \frac{10.2}{\sqrt{25}}$ results in the interval (77.29, 85.71).

Construct a 95% Confidence Interval for the Population Mean μ.\mu.μ. Assume the Population Has a Normal Distribution

Construct a 95% Confidence Interval for the Population Mean $\mu.$ Assume the Population Has a Normal Distribution