Question

The lengths of the products produced in a production process are controlled. The standard deviation is 0.45 mm.

Confidence intervals
ANSWERED
asked 2021-08-02

The lengths of the products produced in a production process are controlled. The standard deviation is 0.45 mm. A quality control specialist keeps checking over 40 units randomly every morning. Average length in one day 35.62mm. when it happens. Which of the following is the confidence interval for the mean population mean at \(\displaystyle{95}\%\) confidence level?
A) \(\displaystyle{P}{\left({60}{<}\mu{<}{70}\right)}={0},{95}\)
B) \(\displaystyle{P}{\left({30}{<}\mu{<}{40}\right)}={0},{05}\)
C) \(\displaystyle{P}{\left({30}{<}\mu{<}{40}\right)}={0},{95}\)
D) \(\displaystyle{P}{\left({60}{<}\mu{<}{70}\right)}={0},{05}\)
E) \(\displaystyle{P}{\left({70}{<}\mu{<}{80}\right)}={0},{95}\)

Expert Answers (1)

2021-08-06
Step 1
It is an important part of statistics. It is widely used.
Step 2
Option C is correct
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The lengths of the products produced in a production process are controlled. The standard deviation is 0.45 mm. A quality control specialist keeps checking over 40 units randomly every morning. Average length in one day 35.62mm. when it happens; Which of the following is the confidence interval for the mean population mean at \(\displaystyle{95}\%\) confidence level?
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