Every week for the last 7 weeks, a random sample of 200 citizens in a county is tested for a virus. The test either comes back positive or negative. The number sampled who tested positive over the last 7 weeks are: 18, 12, 24, 14, 10, 20 and 14. Using 99.73% confidence limits, the county health officer Dr. Cody wants to track to percentage of citizens testing positive for the virus.

1, What type of control chart should Dr. Cody use, and what is the sample size here?

Select one:

a. p-chart

b. xbar-chart

The sample size here

Select one:

a. 50

b. 200

c. 7

d. 100

3,

What is the mean percentage testing positive for the virus?

Select one:

a. 0.16

b. 0.112

c. 0.08

d. 0.04

4,

Using 99.73% confidence, what are the lower and upper control chart limits?

Select one:

a. [0.007, 0.153]

b. [4, 28]

c. [0.042, 0.118]

d. [0.022, 0.138]

5,

What conclusion does Dr. Cody make about the percentage of citizens testing positive for the virus?

Select one:

a. Not enough information to draw a conclusion

b. In control

c. Out of control because theres a change in level

d. Out of control because some values fall outside the control chart limits

c. R-chart

d. c-chart