HP 30b Business Professional Calculator - Manual (Page 31)

Mathematical Calculations 23
Binomial Functions
The binomial function calculates the probability of having up to k successes out of n throws,
when the probability of success is p. Enter n and p each followed by
=
and type k and
navigate to the binomial function in the math menu.
Two-Number Functions
Apart from
+-*/
, the three additional two-number functions accessible on
the keyboard are:
• y
x
• nCr
• nPr
y
x is the power function, nCr stands for the number of combinations of n items taken r at a
time, and nPr stands for the number of permutations of n items taken r at a time.
Combination=
Permutation=
Perform calculations with these functions in the same way you would perform calculations with
+-/
and
*
, but press
:
to access the secondary function key. For
example, to calculate 15
3
:
1. Press
15
.
2. Press
:h
.
3. Press
3=
.
The result is shown in Figure 9.
Figure 9
In RPN mode, key in the numbers first, followed by
I
, then press the function key. For
example, for the power function example above, in RPN press:
15I3:h
.
n!
r! n r
–
( )!
----------------------
n!
n r
–
( )!
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