Use the table below to answer the following questions).
The historical data of Velvetta Inc., a healthcare products manufacturer, have shown that in a production process for filling bottles of shampoo, variance in the volume is constant; however, clogs in the filling machine often affect the mean volume. The historical standard deviation is 5 milliliters. In filling 250-milliliter bottles, a sample of 20 found a mean volume of 242 milliliters. $$\begin{array}{l}\begin{array} { | l | l | }
\hline\text { Velvetta Inc. Shampon }\

\text { Productim } & \
\hline \text { Alpha Vulue } & 0.05 \
\hline \text { Standard Deviation } & 5 \
\hline \text { Sample Size } & 20 \
\hline \text { Sample Mean } & 242 \
\hline
\end{array}
\end{array}$$
-From the table above, calculate the lower confidence interval estimate at a confidence level of 95%
A) 239.49
B) 240.16
C) 239.81
D) 240.04

Question

Use the table below to answer the following questions).
The historical data of Velvetta Inc., a healthcare products manufacturer, have shown that in a production process for filling bottles of shampoo, variance in the volume is constant; however, clogs in the filling machine often affect the mean volume. The historical standard deviation is 5 milliliters. In filling 250-milliliter bottles, a sample of 20 found a mean volume of 242 milliliters. $$\begin{array}{l}\begin{array} { | l | l | } 
\hline\text { Velvetta Inc. Shampon }\

\text { Productim } & \
\hline \text { Alpha Vulue } & 0.05 \
\hline \text { Standard Deviation } & 5 \
\hline \text { Sample Size } & 20 \
\hline \text { Sample Mean } & 242 \
\hline
\end{array}
\end{array}$$
-From the table above, calculate the lower confidence interval estimate at a confidence level of 95%
A) 239.49
B) 240.16
C) 239.81
D) 240.04

Quizplus · Accepted Answer

The lower confidence interval estimate is calculated using the formula: $\bar{x} - z \times \frac{\sigma}{\sqrt{n}}$, where $\bar{x}$ is the sample mean, $z$ is the z-score for the confidence level, $\sigma$ is the standard deviation, and $n$ is the sample size. For a 95% confidence level, the z-score is 1.96. Plugging in the values: $242 - 1.96 \times \frac{5}{\sqrt{20}} \approx 239.81$.

Use the Table Below to Answer the Following Questions) -From the Table Above, Calculate the Lower Confidence Interval Estimate