Answer:
The 95% CI for the difference of means is:
Step-by-step explanation:
<em>The question is incomplete:</em>
<em>"Find a 95% confidence interval on the difference of the towels mean absorbency produced by the two processes. Assumed that the standard deviations are estimated from the data. Round to two decimals places."</em>
Process 1:
- Sample size: 10
- Mean: 200
- S.D.: 15
Process 2:
- Sample size: 4
- Mean: 300
- S.D.: 50
The difference of the sample means is:
The standard deviation can be estimated as:
The degrees of freedom are:
The t-value for a 95% confidence interval and 12 degrees of freedom is t=±2.179.
Then, the confidence interval can be written as: