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

-The producers of the Yugo automobile periodically inspect samples of 80 hoods for dents and scratches. A single flaw in a hood renders it unsuitable for installation in one of their fine automobiles. The results of the last 10 samples are shown below. Calculate the standard error, snp, for the np chart.
A) 7.75
B) 0.10
C) 0.31
D) 2.78
E) 2.95

Question

Use the following table to answer the question(s) below.
 
-The producers of the Yugo automobile periodically inspect samples of 80 hoods for dents and scratches. A single flaw in a hood renders it unsuitable for installation in one of their fine automobiles. The results of the last 10 samples are shown below. Calculate the standard error, snp, for the np chart.
A) 7.75 
B) 0.10 
C) 0.31 
D) 2.78 
E) 2.95

Quizplus · Accepted Answer

The standard error for the np chart is calculated as the square root of (np(1-p)/n), where n is the sample size and p is the proportion of defective items. In this case, n = 80 and p = 0.0375 (since there were 3 defective hoods in the last 10 samples). Therefore, the standard error is sqrt(80 * 0.0375 * (1-0.0375)) = 2.78.

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