The Sample Standard Deviation of the Monthly Sales (In Thousands

Essay

The sample standard deviation of the monthly sales (in thousands of dollars) of a telecommunications firm in the United States for two years, 2010 and 2011, is computed as 6.7. Assuming that the sales data are drawn from a normally distributed population, conduct the following hypothesis tests for the population variance. Use the critical value approach at α = 0.05.
A) H₀: σ² ≤ 25, H_A: σ² > 25
B) H₀: σ² = 36, H_A: σ² ≠ 36