Use the following table to answer the question(s) below.

-A parks and recreation worker counts the number of paint drips on each standard size park bench. The results from the last 10 benches are shown below. If the Parks Department decides to make a c chart, what should the lower and upper 3-sigma control limits be?
A) (-9.2, 9.2)
B) (0.0, 20)
C) (0.1, 18.3)
D) (3.1, 13.1)
E) (3.1, 18.3)

Question

Use the following table to answer the question(s) below.
 
-A parks and recreation worker counts the number of paint drips on each standard size park bench. The results from the last 10 benches are shown below. If the Parks Department decides to make a c chart, what should the lower and upper 3-sigma control limits be?
A) (-9.2, 9.2) 
B) (0.0, 20) 
C) (0.1, 18.3) 
D) (3.1, 13.1) 
E) (3.1, 18.3)

Quizplus · Accepted Answer

To make a c chart, we need the overall average number of paint drips per bench and the average range of the number of paint drips per bench. Using the provided data, we can calculate:

Mean number of paint drips per bench = (0+2+1+4+3+4+2+2+0+1)/10 = 1.9

Range of number of paint drips per bench = Maximum - Minimum = 4 - 0 = 4

Next, we can use these values to calculate the lower and upper 3-sigma control limits:

Lower control limit = mean - 3*sqrt(mean)/sqrt(N) = 1.9 - 3*sqrt(1.9)/sqrt(10) ≈ 0.1

Upper control limit = mean + 3*sqrt(mean)/sqrt(N) = 1.9 + 3*sqrt(1.9)/sqrt(10) ≈ 18.3

Therefore, the answer is C) (0.1, 18.3).

Use the Following Table to Answer the Question(s) Below