Answer:
Kindly check explanation for (1)
2.)
B. We fail to reject the null hypothesis and conclude that there is insufficient evidence at a 0.02 level of significance to support the power company claim that the mean amount of electricity for their residents is more than the national average.
Step-by-step explanation:
1.)
H0 : μ = 10290
H0 : μ > 10290
n = 153, sample mean, xbar = 10586 ; population standard deviation, σ = 2509 ; α = 0.05
Test statistic:
(xbar - μ) ÷ (σ/√(n))
(10586 - 10290) ÷ (2509/√(153))
296 / 202.84062
Test statistic (Z) = 1.46
We obtain the Pvalue :
Decision Region :
Reject H0 ; if Pvalue < α
Pvalue from Z test statistic calculator :
Pvalue = 0.072
Pvalue > α ; Hence, we fail to reject the Null ; there isn't sufficient evidence to support the power company's claim
2.)
H0 : μ = 10290
H0 : μ > 10290
n = 153, sample mean, xbar = 10446 ; population standard deviation, σ = 2509 ; α = 0.02
Test statistic:
(xbar - μ) ÷ (σ/√(n))
(10446 - 10290) ÷ (2509/√(153))
156 / 202.84062
Test statistic (Z) = 0.769
We obtain the Pvalue :
Decision Region :
Reject H0 ; if Pvalue < α
Pvalue from Z test statistic calculator :
Pvalue = 0.221
Pvalue > α ; Hence, we fail to reject the Null ;
B. We fail to reject the null hypothesis and conclude that there is insufficient evidence at a 0.02 level of significance to support the power company claim that the mean amount of electricity for their residents is more than the national average.
