What is the critical value for a two-tailed T-Distribution with 20 degrees of freedom at a 95% confidence level?

To find the critical value for a two-tailed T-Distribution with 20 degrees of freedom at a 95% confidence level, you would typically use a T-Distribution table or a statistical calculator. Here are the steps:

1. Identify the degrees of freedom: In this case, the degrees of freedom is 20.

2. Identify the confidence level: The confidence level is 95%. Because it's a two-tailed test, you want the total area in both tails, not just one. So, you need to adjust the confidence level to account for both tails of the distribution. This means you want to find the t-value that leaves 2.5% in each tail (5% total in both tails), which corresponds to a 97.5% confidence level for a one-tailed test.

3. Look up the corresponding t-value: Using a T-Distribution table or a statistical calculator, look up the t-value that corresponds to 20 degrees of freedom and a 97.5% confidence level.

According to most T-Distribution tables or statistical calculators, the t-value that corresponds to 20 degrees of freedom and a 97.5% confidence level is approximately 2.086.

So, the critical value for a two-tailed T-Distribution with 20 degrees of freedom at a 95% confidence level is approximately 2.086.