Amanager of a grocery store wants to determine if consumers are spending more than the national average. the national average is $150.00 with a standard deviation of $30.20. the manager collects 40 random receipts and finds that the average is $160. complete a hypothesis test with a significance level of 2.5% to determine if the average customer spends more in his store than the national average. which of the following is a valid conclusion for the manager based on this test?

a. the customers spend more than the national average in his store. b.the manager should decrease prices in his store. c.the customers do not spend more than the national average in his store. d.the customers in his store just come from a rich neighborhood.

The correct answer is:

The customers spend more than the national average in his store

Step-by-step explanation:

The national average is $150.00 with a standard deviation of $30.20.

Sample size n =40

H0: x bar = mu

Ha: x bar >mu

(one tailed test for a single mean)

Sample average x bar = 160

Mean difference = 160-150 =10

std error = 30.20/sqrt 40

=4.775

Test statistic = 2.094

Z critical for 2.5% = 1.96 (one tailed)

Since test statistic > z critical we reject null hypothesis.

Hence the correct answer is:

The customers spend more than the national average in his store.

idk but i found this "the graph of y = f(x-2) is the graph of y = f(x) translated two units rightward.  

so, since the point (9,2) lies on the graph of y = f(x), the point (11,2) lies on the graph of y = f(x-2)."

step-by-step explanation:

link is