Section 3: Automatic Memory Stack and ALPHA Register53
Keystrokes Display    
287 ENTER   287.0000    
12.9  ÷   22.2481   Oops! The wrong number.
g LASTX   12.9000   Retrieves the last entry.
 ×    287.0000   You are back at the beginning.
13.9  ÷   20.6475   The correct answer.
Remember, if you key in the wrong digits and discover them prior to executing a function, you can use    to edit the number.
In the above axample, when first  ÷  is pressed, followed by g LASTX, the contents of the stack and LAST X registers are changed...
  ...from this... this... this...  
  T  0.0000         T  0.0000         T  0.0000  
  Z  0.0000         Z  0.0000         Z  0.0000  
  Y  287.0000       Y  0.0000         Y  22.2481  
  X  12.9000    ÷      X  22.2481   g  LASTX  X  12.9000  
LAST X   12.9000
Recovering a Number for Calculation
The LAST X register is useful in calculations where a number occurs more than once. By recovering a number using LASTX , you do not have to key that number into the calculator again.
For example, calculate
  96.704 + 52.394706  
Keystrokes Display    
96.704 ENTER   96.7040    
52.394706  +   149.0987   Intermediate answer.
g LASTX   52.3947   Recalls 52.394706 to the X-register.
 ÷    2.8457   The answer.
Constant Arithmetic
You may have noticed that whenever the stack drops because of a two-number operation (not a R  ), the number in the T-register is reproduced there. This stack operation can be used to insert a constant into a problem.