Concept explainers
a
Interpretation:
Acceptability of heavy duty nails lot
Concept Introduction:
Normal distribution is the probability function with continuous series. It is bell shaped distribution function where mean, median and mode are same.
a
Answer to Problem 67AP
Explanation of Solution
Given information:
n = 100
c= 2
AQL = 1%
LTPD = 10%
and
Lot size, N=10,000
Accepted Quality Level (AQL) is 1%
Lot Tolerance Percent Defective (LTPD) is 10%
Hence,
b
Interpretation:
Sequential sampling plan
Concept Introduction:
Normal distribution is the probability function with continuous series. It is bell shaped distribution function where mean, median and mode are same.
b
Answer to Problem 67AP
Sequential sampling plan with two limit lines are
Explanation of Solution
Given information:
n = 100
c= 2
AQL = 1%
LTPD = 10%
Computation of two lines
Calculate the values of k,
Information known as per the problem
Now, substitute these values in equation (1) to calculate k as shown below
Now, substitute these values in equation (2) to calculate
Now, substitute these values in equation (3) to calculate
=
Similarly, substitute these values in equation (4) to calculate s as shown below:
Calculate the two limit lines by substituting the values of 2.42, 1.051 and 0.0397 in the
Hence, the two limit lines are
c
Interpretation:
Maximum value of the expected sample size
Concept Introduction:
Normal distribution is the probability function with continuous series. It is bell shaped distribution function where mean, median and mode are same.
c
Answer to Problem 67AP
The maximum expected number of items which must be sampled is probably less than 75.
Explanation of Solution
Given information:
n = 100
c= 2
AQL = 1%
LTPD = 10%
At p=0 ASN=60.86
At p=0.1 ASN=71.97
At p=0.0397 ASN=66.6
Based on this, the maximum expected number of items which must be sampled is probably less than 75.
d
Interpretation:
Graphical representation of acceptance and rejection region and check whether sequential sampling plan would recommend acceptance or rejection on or before testing 100th nail.
Concept Introduction:
Normal distribution is the probability function with continuous series. It is bell shaped distribution function where mean, median and mode are same.
d
Explanation of Solution
Hence, acceptance would be recommended on 61st nail.
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Chapter 12 Solutions
Production and Operations Analysis, Seventh Edition
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