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HOW TO PERFORM TWO SAMPLE T TEST USING DATA WITH TI83 CALCULATOR

Steps Key Sequence Screens
1. Enter data into list, L1    
2. Enter data into list, L2    
3. Set up Stats Tests STAT
  twice
  4 (for 2–SampTTest...)
4. Select Data use left arrow key (if necessary) to move cursor to Data, then ENTER
5. Select list, L1 (press ALPHA), then 2nd, then 1, then ENTER
6. Select list, L2 (press ALPHA), then 2nd, then 2, then ENTER
7. Select test Press twice, then using arrow keys, select desired test, then ENTER
8. Enter no for Pooled use left arrow key (if necessary) to move cursor to No, then ENTER
9. Calculate P–value once, ENTER
10. Scroll down to find more calculations Press
In this case, the test was Ha: μ1 < μ2; the t statistic is 4.282; the p–value is 0.99994; the df is 39.06, etc.