Texas Instruments TI-82 STATS Manual Book page 259

(two-proportion z confidence interval; item )
2.PropZInt
2.PropZInt B
computes a confidence interval for the difference between the
proportion of successes in two populations (p ). It takes as
Np
1 2
input the count of successes in each sample (x and x ) and the
1 2
count of observations in each sample (n and n ). The computed
1 2
confidence interval depends on the user-specified confidence
level.
Input:
,
Calculated results:
Inferential Statistics and Distributions 13–21