HP 39g Graphing Calculator - Manual (Page 137)

Two-Sampie T-Interva!
Menu name T-INT: |il -jx2
This option uses the Student’s t-distribution to calculate a
confidence interval for the difference between the means of
two populations, pj - P
2
> when the population standard
deviations, Ojand Gj, are unknown.
Inputs The inputs are:
Field name Definition
11
Sample 1 mean.
X 2
Sample 2 mean.
sl Sample 1 standard deviation.
s
2
Sample 2 standard deviation.
nl Sample 1 size.
n
2
Sample 2 size.
c
Confidence level.
„Pooled Whether or not to pool the samples based
on their standard deviations.
Results
The results are:
Result Description
Critical T Critical value for T.
ApMin Lower bound for P| - P
2
.
A p Max Upper bound for P| -- P
2
-
Inference aplet 9-21