I do not understand how the xbar of 139.2 and the sample standard deviation of 9.20 were found. Can anyone help me to understand how this information was found by the information that was given in section A?

Significance Test for t (One Sample)

xbar 139.2

Hypothesized Value 140

Sample Standard Deviation 9.20

n 30

Significance Level (alpha) 0.01

Number of Tails 2 df 29

Test Statistic (t) -0.47628048

P-Value (Left) 0.63744347 3

Critical Value 2.75638590 4

Confidence Interval for t (One Sample)

Sample Mean (xbar) 139.2

Sample STDEV (s) 9.2

n 30

Confidence Level 0.99

df 29

tstar 2.75638590 4

Lower Limit 134.570146 8

Upper Limit 143.829853 2

PART A: THE TEST

The test being conducted today will help to determine reliability of being able to diagnose patients with diabetes through the form of blood testing. My test includes 30 patients to be tested for diabetes through their blood. The data was conducted using a randomize sample of glucose readings between 125 - 145. I was able to get a STD DEV (9.2). Above table will show the starting values to begin the testing process. The decision to use the t-test was based on having unknow data for sigma.