HP 20B User Manual

Mathematical Calculations
19
When an operation is performed on the stack, addition (+)for instance, the calculator "pops" or moves the two numbers
from the bottom levels (Levels 1 and 2) out of the stack, performs the operation, and "pushes" the results back into the stack.
With the numbers entered into the stack as shown in Figure 3, pressing + changes the stack as shown in Figure 4. Note
that when the numbers are "popped" out to add 23 and 41, Level 4 of the stack remains unchanged.
-15
-15
12
64
Figure 4 The RPN Stack of Figure 3 after the Addition Operation
Last Number
Each time you perform a mathematical operation, the content of Level 1 of the stack is saved. Pressing :d recalls that
number. This functionality can be used to undo an erroneous key press, or if you want to reuse a number, such as 56.123 in
the expression:


  123.56
123.5623.1

See Table 2-2 for an example using the last number function.
Table 2-2 Last Number
Keys Display Description
:u3I
Sets FIX= to 3.000
<<<<<
II
Selects RPN as the operating mode.
O1c23
I56c1
23
Inputs 1.23 and 56.123

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

Summary

Legal Notices

Revision History

Details of revisions made to the manual.

HP 20b Business Consultant Keyboard

Keyboard Map Legend

Explains the features and functions of each key on the calculator.

Basic Features

Turning the Calculator On and Off

Instructions for powering the calculator on and off.

Selecting a Language

Guide to changing the display language.

The Mode Menu: Setting Preferences

Customizing calculator settings like display precision and modes.

Key Presses and the Secondary Function Key

Explains how to use primary and secondary key functions.

Memory and the Memory Menu

Details on accessing and using the calculator's memory.

Mathematical Calculations

Mathematical Functions

Overview of available mathematical operations.

Number Entry and Display

How to input and view numbers.

Reverse Polish Notation (RPN) Mode

Explanation of RPN calculation mode and its stack.

Storing and Recalling Numbers

Methods for saving and retrieving numbers.

Percentages

How to perform percentage calculations.

Time Value of Money

Time Value of Money (TVM) Keys

Introduction to TVM functions and cash flow diagrams.

Calculating Payments on a Loan

Step-by-step guide for loan payment calculations.

Amortization

Details on creating and viewing amortization schedules.

Cash Flows

Cash Flow Example

Demonstrates entering and analyzing cash flow data.

Analyzing Cash Flows

Using NPV and IRR functions for cash flow analysis.

NPV and IRR Menus

Menu structure for Net Present Value and Internal Rate of Return.

Bonds

The Bond Menu

Guide to accessing and using the bond calculation menu.

Bond Calculation Example

Example showing how to calculate bond prices.

Date Calculation

The Date Calculation Menu

How to use the menu for date-related calculations.

Date Calculation Example

Example of calculating days between dates.

Break-even

The Break-even Menu

Menu for break-even analysis.

Break-even Example

Demonstrates solving break-even problems.

Business Problems

The Percent Calculation Menu

Menu for markup, percent change, and part/total calculations.

Percent Calculation Examples

Examples of business percentage calculations.

Depreciation

The Depreciation Menu

Menu for various depreciation calculation methods.

Depreciation Methods

Brief descriptions of depreciation calculation methods.

Depreciation Example

Step-by-step example of depreciation calculation.

Statistical Operations

The Data and Stats Menus

Accessing menus for statistical analysis.

Statistics Menu Items

List and description of statistical calculation options.

Statistics Example

Example of performing statistical analysis and predictions.

Errors

Error Messages and Calculator Status

List and explanations of calculator error messages.

Warranty, Regulatory, and Contact Information

Replacing the Batteries

Instructions for safely replacing calculator batteries.

HP Limited Hardware Warranty and Customer Care

Information about the product warranty and customer support.

Contact Information

List of contact details for customer support by region.

Product Regulatory & Environment Information

Details on regulatory compliance and environmental standards.