User`s guide
At a Glance...
19
Probability
Enter .5 as a Z-value and calculate the cumulative probability of the Z-value and the Z-value 
from a given cumulative probability.
For more information on probability, refer to the section titled, Probability in chapter 12, 
Statistical Calculations.
Table 1-32 Probability keys
Keys Description
]F
Calculates a cumulative normal probability 
given a Z-value.
]o
F
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.
]o
I
Calculates a T-value given degrees of 
freedom and the cumulative Student’s T 
probability.
]<
Calculates number of permutations of n items 
taken 
r at a time.
]9
Calculates number of combinations of n taken 
r at a time.
]E
Calculates factorial of n (where -253 < n < 
253).
Table 1-33 Calculating the probability
Keys Display Description
\5V
0.00000 Sets number display to five 
digits to the right of the 
decimal.
7V]F
.69146 Calculates the cumulative 
probability of the Z-value.
17GV4
.94146 Adds .25.
]oF
1.56717 Calculates the Z-value from 
the cumulative probability.










