Incorrect Question 25 013 s n a random sample of 15 computers, the mean repair c
ID: 3338731 • Letter: I
Question
Incorrect Question 25 013 s n a random sample of 15 computers, the mean repair cost was $100 and the standard deviation was $42.50. Assume that the repair cost of computers follows a normal distribution. All other information remaining unchanged, which of the following would produce a narrower interval than the 95% confidence interval constructed? The sample standard deviation is computed to be 30 instead of 42.50 The sample size is 10 instead of 15 compute a 98% confidence interval rather than a 95% confidence interval. The sample size is 28 instead of 15Explanation / Answer
To narrower confidence interval either increase sample size or decrease confidence level.
From the available options in question.
Answer- Sample size is 28 instead 15.
(By increasing confidence level, confidence interval will be wider.)