An HR practitioner would like to construct a confidence interval (CI) estimate for salaries of data scientists. In a sample of 20 data scientists, the average salary is R800 per annum with a standard deviation of R238 per annum. Construct a 90% CI estimate of data scientists' salaries and choose the correct answer from the list of options below. a. (712.46; 887.54) b. (695.69; 904.31) c. (662.91; 937.09) d. (707.99; 892.01) e. (688.61; 911.39)
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Step 1: The formula for a confidence interval is: $$CI = \bar{x} \pm z_{\alpha/2} \frac{s}{\sqrt{n}}$$ where: * $\bar{x}$ is the sample mean * $s$ is the sample standard deviation * $n$ is the sample size * $z_{\alpha/2}$ is the critical value from the standard Show more…
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