HP 20B User Manual

Mathematical Calculations
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Figure 6 The RPN Stack and the Roll Down Operation
Pressing ) performs a swap . A swap operation exchanges the numbers on Levels 1 and 2 of the stack. The ) key has
a small symbol on it as a reminder of the swap feature. With the numbers entered into the stack shown in the left column in
Figure 7, pressing ) performs a swap to the stack as shown in the right column.
Figure 7 The RPN Stack and the Swap Operation
Note: when no menu is selected, the < key performs the same function as the ( key. The > key performs the
inverse operation called, roll up .
One-Number Functions and the Math Menu
The key presses for the one-number mathematical functions listed in Table 2-4 below apply to all modes, Chain, Algebraic,
and RPN. To execute one-number functions, with a number displayed, press the key or key combination corresponding to the
operation you wish to execute. The result is displayed on the bottom line.

HP 20B Specifications

General

Type	Financial
Cover	-
Form factor	Pocket
Control type	Buttons
Product color	Black
Digits	12 digits
Display type	LCD
Display tilting	No
Display number of lines	2 lines
Battery type	CR2032
Power source	Battery
Auto power off	Yes
Number of batteries supported	2
Memory registers	110

Weight and Dimensions

Depth	149.2 mm
Width	77 mm
Height	16 mm
Weight	37.5 g