Construct a 90% Confidence Interval for the mean diamond price.

Population standard deviation is unknown.

n (sample size) = 308

Mean =5,019.48

Sample std dev = 3,403.12

Student T-Value Calculator You can use this T-Value Calculator to calculate the Student's t-value based on the significance level and the degrees of freedom in the standard deviation. How to use the calculator 1. Enter the degrees of freedom (df) 2. Enter the significance level alpha (a is a number between 0 and 1) 3. Click the "Calculate" button to calculate the Student's t-critical value. Online T-Value Calculator Degrees of Freedom (df): 307 Significance Level (a): 0.1 Calculate Reset Results T-Value (right-tailed): 1.284315 T-Value (two-tailed): +/- 1.649832