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 manager of a grocery store wants to determine if consumers are spending more than the national average.

Yes is the answer

Step-by-step explanation:

Given that 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 Manager's contention is right.

We conclude that consumers are spending more than the national average.      

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = $150.00

Sample mean, = $160

Sample size, n = 40

Alpha, α = 0.025

Population standard deviation, σ = $30.20

First, we design the null and the alternate hypothesis

We use One-tailed z test to perform this hypothesis.

Formula:

Putting all the values, we have

Now,

Since,  

We reject the null hypothesis and accept the alternate hypothesis. We conclude that consumers are spending more than the national average.

whatvare the choices

step-by-step explanation: