HP 35s User Manual page 163

The result of an operation is always an integer (any fractional portion is
truncated).
Whereas conversions change only the display of the number but not the actual
number in the X–register, arithmetic does alter the number in the X–register.
If the result of an operation cannot be represented in valid bits, the display shows
 and then shows the largest positive or negative number possible.
Example:
Here are some examples of arithmetic in Hexadecimal, Octal, and Binary modes:
Keys:

()


()
 
()

()

 
()
 


()
 
()

()


()
12F
16
7760

()
100
5A0
16

Base Conversions and Arithmetic and Logic
= ?
+ E9A
16
Display:
Sets base 16; HEX
annunciator on.
Result.

– 4326 =?
8 8
Sets base 8; OCT

annunciator on. Converts
displayed number to octal.

Result.
÷ 5 =?
8 8
 Integer part of result.
+ 1001100 =?
2
Sets base 16; HEX

annunciator on.
Description:
11-5