30  Getting Started
For more information on statistical calculations, refer to chapter 12, Statistical 
Calculations in the HP 10bII+ Financial Calculator User’s Guide.
Probability
\«
55.68 Displays sample 
standard deviation of 
y.
\T\«
-10.00 Displays y-intercept 
of regression line.
\W\«
-27.50 Displays slope of 
regression line.
]f
1,420.00 Displays  xy, sum 
of the products of 
x- 
and 
y-values.
Table 1-32 Probability keys
Keys Description
]F
Calculates a cumulative normal probability given a Z-
value.
]oF
Calculates a Z-value given a cumulative normal 
probability.
]I
Calculates the cumulative Student’s T probability given 
degrees of freedom and a T-value.
]oI
Calculates a T-value given degrees of freedom and the 
cumulative Student’s T probability.
Table 1-31 Statistics example
Keys Display Description