Answer:
C) µ = 8000.
Step-by-step explanation:
Explanation:-
Given data A grocery store has an average sales of $8000 per day
mean of the Population μ = $ 8000
sample size 'n' = 64
mean of the sample x⁻ = $ 8300
Null Hypothesis : H₀ : μ = $ 8000
Alternative Hypothesis : H₁: μ > $ 8000
Test statistic
[tex]Z = \frac{x^{-} -mean}{\frac{S.D}{\sqrt{n} } }[/tex]
[tex]Z = \frac{8300 -8000}{\frac{1200}{\sqrt{64} } }[/tex]
Z = 2
Level of significance : ∝ = 0.05
Z₀.₀₅ = 1.96
The calculated value Z = 2 > 1.96 at 0.05 level of significance
Null hypothesis is rejected
Alternative hypothesis is accepted at 0.05 level of significance
Conclusion :-
The advertising campaigns have been effective in increasing sales