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HOW TO FIND ONE SAMPLE T CONFIDENCE INTERVALS USING DATA WITH TI83 CALCULATOR

Steps Key Sequence Screens
1. Enter data into list, L1    
2. Set up Stats Tests STAT
  twice
  8 (for TInterval...)
3. Select Inpt, DATA left arrow once (if necessary), then ENTER
4. Select list, L1 once, (press ALPHA), then 2nd, then 1, then ENTER
5. Input confidence level once, enter confidence level (AS DECIMAL), then ENTER
6. Calculate CI ENTER
In this case the 90% CI is 24.666 to 64.214; the mean of the sample is 44.44; the standard deviation of the sample is 20.741 and the sample size is 5.