Essay
A company employs two shifts of workers. Each shift produces a type of gasket where the thickness is the critical dimension. The average thickness and the standard deviation of thickness for shift 1, based on a random sample of 40 gaskets, are 10.85 mm and 0.16 mm, respectively. The similar figures for shift 2, based on a random sample of 30 gaskets, are 10.90 mm and 0.19 mm. Let 
be the difference in thickness between shifts 1 and 2, and assume that the population variances are equal.
-(A) Construct a 95% confidence interval for 
.
(B) Based on your answer to (A), are you convinced that the gaskets from shift 2 are, on average, wider than those from shift 1? Why or why not?
Correct Answer:
Verified
(A) 
The pooled standard deviation is ...View Answer
Unlock this answer now
Get Access to more Verified Answers free of charge
Correct Answer:
Verified
The pooled standard deviation is ...View Answer
Unlock this answer now
Get Access to more Verified Answers free of charge
Q21: The t-distribution for developing a confidence interval
Q22: In order to construct a confidence interval
Q23: (A) Construct a 90% confidence interval for
Q24: When the samples we want to compare
Q25: The interval estimate 18.5 <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB1387/.jpg" alt="The
Q28: If you decrease the confidence level, the
Q30: After calculating the sample size needed to
Q30: A 90% confidence interval estimate for a
Q31: (A) Determine a 95% confidence interval for
Q54: If two samples contain the same number