HP 35s User Manual page 169

To correct statistical data:
1. Reenter the incorrect data, but instead of pressing
deletes the value(s) and decrements n.
2. Enter the correct value(s) using
If the incorrect values were the ones just entered, press
them, then press
register, and its x–value was saved in the LAST X register.) After deleting the
incorrect statistical data, calculator will display the value of Y-register in line 1 and
value of n in line 2.
Example:
Key in the x, y–values on the left, then make the corrections shown on the right:
Initial x, y
Keys:
 
()








 
to delete them. (The incorrect y–value was still in the Y–
20, 4
400, 6













.
Display:
Statistical Operations
  
, press
 
to retrieve
Corrected x, y
20, 5
40, 6
Description:
Clears existing statistical
data.
Enters the first new data pair.
Display shows n, the number
of data pairs you entered.
Brings back last x–value. Last
y is still in Y–register.
Deletes the last data pair.
Reenters the last data pair.
Deletes the first data pair.
. This
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