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HOW TO FIND TWO SAMPLE T CONFIDENCE INTERVALS WITH TI83 CALCULATOR

Steps Key Sequence Screens
1. Set up Stats Tests STAT
  twice
  0 (for 2–SampTInt...)
2. Select Stats for Input once (if necessary), then ENTER
3. Input mean of SAMPLE once, enter mean of SAMPLE1, then ENTER
4. Input standard deviation enter standard devation of SAMPLE1, then ENTER
5. Input sample size enter sample size of SAMPLE1, then ENTER
6. Input mean of SAMPLE enter mean of SAMPLE2, then ENTER
7. Input standard deviation enter standard devation of SAMPLE2, then ENTER
8. Input sample size enter sample size of SAMPLE2, then ENTER
9. Input confidence level enter confidence level (AS DECIMAL), then ENTER
10. Enter no for Pooled press ENTER on No
11. Calculate CI once, ENTER
12. Scroll down to find more calculations Press
In this case the 95% CI is –12.28 to 27.083.