Question

a company claims that the mean monthly residential electricity consumption in a certain region is more than 880 kilowatt - hours (kwh). you want to test this claim. you find that a random sample of 70 residential customers has a mean monthly consumption of 910 kwh. assume the population standard deviation is 124 kwh. at \\( \alpha = 0.05 \\), can you support the claim? complete parts (a) through (e).
(a) identify \\( h_0 \\) and \\( h_a \\). choose the correct answer below.
\\( \bigcirc \\) a. \\( h_0: \mu>910 \\) (claim) \\( h_a: \mu\leq910 \\)
\\( \bigcirc \\) b. \\( h_0: \mu>880 \\) (claim) \\( h_a: \mu\leq880 \\)
\\( \bigcirc \\) c. \\( h_0: \mu\leq910 \\) \\( h_a: \mu>910 \\) (claim)
\\( \bigcirc \\) d. \\( h_0: \mu = 880 \\) (claim) \\( h_a: \mu\
eq880 \\)
\\( \bigcirc \\) e. \\( h_0: \mu\leq880 \\) \\( h_a: \mu>880 \\) (claim)
\\( \bigcirc \\) f. \\( h_0: \mu = 910 \\) \\( h_a: \mu\
eq910 \\) (claim)

Explanation:

• The null hypothesis \(H_0\) is a statement of equality or non - effect. The alternative hypothesis \(H_a\) is the claim we are trying to find evidence for.
• The company's claim is that the mean monthly residential electricity consumption \(\mu>880\). In hypothesis testing, the null hypothesis is the opposite of the claim (when the claim is in the alternative). So \(H_0:\mu\leq880\) and \(H_a:\mu > 880\) (where \(H_a\) is the claim).

Answer:

E. \(H_0:\mu\leq880\), \(H_a:\mu > 880\) (claim)