HP 17bII+ - Manual (Page 46)

46 2: Arithmetic
File name : English-M02-1-040308(Print).doc Print data : 2004/3/9
The s and R keys can also be used with variables. For example,
s  (in the MU%C menu) stores the rightmost number from the
display into the variable M%C. R  copies the contents of
M%C into the calculator line. If there is an expression in the display
(such as ), then the recalled number replaces only the last
number.
You do not need to clear storage registers before using them. By storing
a number into a register, you overwrite whatever existed there before.
Doing Arithmetic Inside Registers and Variables
You can also do arithmetic inside storage registers.
Keys: Display: Description:
45.7 s 3 
Stores 45.7 in reg. 3.
2.5 s* 3

Multiplies contents of
register 3 by 2.5 and stores
result (114.25) back in
register 3.
R 3 
Displays register 3.
Table 2-3. Arithmetic in Registers
Keys New Register Contents
s+ old register contents + displayed number
s- old register contents – displayed number
s* old register contents x displayed number
s/ old register contents ÷ displayed number
s @u old register contents ^ displayed number
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