A lightbulb manufacturer wants to estimate the total number of defective bulbs contained in all of the boxes shipped by the comp
any during the past week. Production personnel at this company have recorded the number of defective bulbs found in each of 50 randomly selected boxes shipped during the past week. These data are provided in the file P08_12.xlsx. Calculate a 95% confidence interval for the total number of defective bulbs contained in the 1000 boxes shipped by this company during the past week. Hint: Note that sample size is 50 and population size is 1000. The question is asking for a confidence interval for a total.
1 answer:
Answer: we are 95% confident that the total number of defective bulb
contained in the 1000 boxes shipped by this company is between 195.5 and 644.5
Step-by-step explanation:
The sample size n = 50
The population size N= 1000
The number of defective in the sample is 21.
Sample mean x bar= 21/50
=0.42
The standard deviation (sigma) is = 0.81
Calculating the confidence interval
By checking the attached picture below.
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