HP 39g+ - Manual (Page 130)

9-16 Inference aplet
Confidence intervals
The confidence interval calculations that the HP 39G/40G can
perform are based on the Normal Z–distribution or Student’s
t–distribution.
One–Sample Z–Interval
Menu name Z–INT: 1
µ
This option uses the Normal Z–distribution to calculate a
confidence interval for
µ
, the true mean of a population, when
the true population standard deviation,
σ
, is known.
Inputs The inputs are:
Results The results are:
Field name Definition
Sample mean.
σ
Population standard deviation.
n Sample size.
C Confidence level.
x
Result Description
Critical Z Critical value for Z.
µ
min Lower bound for
µ
.
µ
max Upper bound for
µ
.