Answer:
Yes, this sample provide enough evidence to support the delivery time claim made by the pizza place.
Step-by-step explanation:
We are given that a pizza place recently hired additional drivers and as a result now claims that its average delivery time for orders is under 44 minutes.
A sample of 39 customer deliveries was examined, and the average delivery time was found to be 40.5 minutes. Historically, the standard deviation for delivery time is 11.3 minutes.
From this, X bar = 40.5 , = 11.3 ,
= 44 and sample, n = 39
Null Hypothesis, :
>= 44
Alternate Hypothesis, :
< 44
The test statistics used here will be;
T.S. = ~ N(0,1)
So, Test statistics = = -1.93
Now, at 5% significance level the z score table gives critical value of -1.6449 as it is one-tail test.
<em>Since our test statistics is less than the critical value as -1.93 < -1.6449, so we have sufficient evidence to reject null hypothesis and conclude that the average delivery time for orders is under 44 minutes.</em>