HP 20B Recall Arithmetic, Storing and Recalling with Time Value of Money TVM Keys, Percentages

Mathematical Calculations

press L2to recall memory 2. Note how the new current value stored in memory 2 is 17, (5 +12). +-*and

/are valid mathematical operations for memories.

To view the stored values in memories 1-9 and 0, press :t, followed by <or >repeatedly to scroll through each memory starting with memory 1 (Mem 1 ). Note that in the Memory menu, you can change the value of any memory by selecting the memory and typing a number followed by the tkey.

Recall Arithmetic

In RPN, typing 12L+2adds the value of memory 2 to the first level of the stack, but it will not modify the stored value of memory 2. This is useful, as it "saves" one stack level. You can also use -*and /after L.

To perform the same operation in Algebraic and Chain modes, press 12+L2=.

Storing and Recalling with Time Value of Money (TVM) Keys

To store the current number in the Time Value of Money (TVM) variables, press :$followed by the desired TVM key.

To recall the stored value of a TVM variable, press Lfollowed by the key of the desired TVM variable. Note: pressing L does not calculate the variable; it recalls the current value.

Recalling a Menu Item Value in a Menu

In a menu, you can recall the current value of a menu item. For example, open the Interest Conversion menu (IConv) by pressing :&. With Nom.% displayed, pressing 2*L=recalls the nominal rate. This feature is useful when you need to insert the contents of a menu item into an algebraic operation.

Rounding Numbers

All calculations are performed internally with 15-digit precision and are rounded to 12 digits when returning the results. In certain instances, calculations are performed internally with greater than 15-digit precision.

When displayed, a number is further rounded to the number of digits after the decimal point set by the FIX item in the Mode menu. The default setting is two digits to the right of the decimal point. For more information, refer to the section titled, The Mode Menu: Setting Preferences in Chapter 1.

Note: the FIX setting only affects the display; it does not affect the actual numbers.

Percentages

In Algebraic or Chain modes, pressing %divides a number by 100. For example, pressing 25%returns 0.25.

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