Question 1
2 The company policy for customer service representatives gives time off for positive reviews. If, in the first 20 calls a customer service agent handles In a day, 13 or more elect to take a subsequent survey and rate the service as "excellent," then the company gives the agent his or her final hour of work that day off, paid. Ellie receives excellent reviews from about 30% of the calls she handles. Assuming she always receives at least 20 calls in the first 7 hours of a workday, on what percentage of her 8-hour workdays does Ellie get the final hour off?

Question 2
A quality control analyst measures the number of hours a patient in a low-risk condition waits for care at the emergency room of a small hospital. The following data are obtained for 20 patients.

2.26 2.01 3.0 1.22 1.92 1.79 0.78 1.89 0.71 1.58
2.02 2.77 2.87 0.51 0.74 1.95 2.76 2.61 3.54 2.95

a. compute the sample mean, sample median, and range of data.
b. compute the sample standard deviation and sample variance.

Question 3
Since careful records have begun being kept in January, Eric's small business
has delivered the following quantities of flowers throughout town.


January
February
March
April
May
June
July
August
Small
Bouquets
85
34
26
24
43
29
30
19
LargeI.
Bouquets
23
64
27
18
33
23
20
13
Assuming the data is normally distributed, construct two separate 90% confidence intervals, one for the number of deliveries of small bouquets in September and one for the number of large bouquets in
September.
Question 4
Consider the following data values of variables x and y
x: 5 4 3 6 9 8 10
y: 7 8 10 5 2 3 1
Construct a scatter diagram of the data points and plot the least squares regression line on it. Find the least squares regression line.


Question 5
Assume the number of sales per day of an app in the apple iOS App is normally distributed.

1.what two parameters of distribution would you need to be able to determine the probability of sales on a particular day exceeding 100 units?

2.If the probability of sales exceeding 100 units is 20% and the mean daily sales is 86 units, then what is the standard deviation of the distribution?


Question 6


researchers are studying a new chemical process for producing dyes. Although they don't know it, the yield of the process is normally distributed with IJ =550kg and a = 75kg. The researchers plan to estimate the process's mean yield by running the ~,process 35 times, recording the yield each time. Have they chosen a large enough sarnple to be 90% confident that their computed mean will be within 20kg of the actual '11ean? Show your work to justify your answer.