Author Question: One of the most important aspects of quality improvement is the idea of reducing the variability in ... (Read 59 times)

Melani1276 · **on:** Jun 24, 2018

One of the most important aspects of quality improvement is the idea of reducing the variability in a product or service. For instance, a major bank has worked to reduce the variability in the service time at the drive-through.

The managers believe that the standard deviation in service time should not exceed 30 seconds. To test whether this goal is being achieved, a random sample of n = 25 cars is selected each week and the service time for each car is measured. Last week, the mean time was 345 seconds with a standard deviation equal to 38 seconds. Given this information, if the significance level is 0.10, the critical value from the chi-square table is about 34.3. Indicate whether the statement is true or false

Question 2

An animal shelter wants to estimate the mean number of animals housed daily and they know the standard deviation. If they want to find a 98 percent confidence interval the critical value to use is:

A) 1.645
B) 1.98
C) 2.33
D) 2.575