Final answer:
The value for x2 at a 98% confidence interval with a sample size of 12 is found using a t-distribution table or statistical software. It is used in conjunction with the sample mean and standard deviation to calculate the confidence interval for the population mean.
Step-by-step explanation:
The value for x2 for a 98% confidence interval when n=12 is not explicitly provided, but can be obtained by referring to a t-distribution table or using statistical software to find the t-score that corresponds to the 98% confidence level with n-1 degrees of freedom, which in this case would be 11 degrees of freedom. The t-score can then be used to calculate the confidence interval for the population mean based on a sample mean and standard deviation.
In general, to find the 98% confidence interval for a population mean, one would use the formula: mean ± (t-score * (sample standard deviation / sqrt(n))). However, without the sample mean or standard deviation, we cannot provide the specific interval.
It's important to remember that confidence intervals vary in width with both the level of confidence and the sample size; higher confidence levels result in wider intervals, while larger sample sizes tend to produce narrower intervals.