User's Manual

Inference app 253

Confidence intervals

The confidence interval calculations that the HP Prime can

perform are based on the Normal Z-distribution or

Student’s t-distribution.

One-Sample Z-Interval

Menu name Z-Int: 

This option uses the Normal Z-distribution to calculate a

confidence interval for , the true mean of a population,

when the true population standard deviation, , is known.

Inputs The inputs are:

Results The results are:

Two-Sample Z-Interval

Menu name Z-Int: 

– 

This option uses the Normal Z-distribution to calculate a

confidence interval for the difference between the means

of two populations, 



–



, when the population standard

deviations, 

and 

, are known.

Field

name

Definition

Sample mean

n Sample size

 Population standard deviation

C Confidence level

Result Description

CConfidence level

Critical Z Critical values for Z

Lower Lower bound for 

Upper Upper bound for 