Answer
$\bar{x}$ = 1456.49/14=104.035 , μ=95, s = $\sqrt \frac{154949.9185-(104.035^{2}/14}{13}=16.22$, $σ_\bar{s}$=$\frac{16.2291}{\sqrt 14}$=4.3374, n=14
α = 0.05 , df = 14-1=13, critical value= 3.012
t =$\frac{\bar{x}-μ }{σ_\bar{s}}$=$\frac{104.035-95}{4.3374}$
= 1.10
H0: μ<=95
H1: μ > 95
for α = 0.05
Non rejection region = t < 3.012
Rejection region = t > 3.012
since t = 1.1 < 3.012, we failed to reject H0 and conclude the average amount of money spent by all customers at this supermarket after the campaign was started is not more than 95 dollars.
Work Step by Step
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