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HOW TO FIND THE CONFIDENCE INTERVAL FOR ONE SAMPLE PROPORTION WITH TI83 CALCULATOR

Steps Key Sequence Screens
1. Set up Stats Tests STAT
  twice
  ALPHA, then MATH (for 1–PropZInt...)
2. Input number of successes, x enter value for x, then ENTER
3. Input number of observations in SAMPLE, n enter value for n, then ENTER
4. Input confidence level enter confidence level (AS DECIMAL), then ENTER
5. Calculate confidence interval ENTER
In this case, the 95% CI is from 0.49151 to 0.52235; is 0.5069 and n is 4040.