Meanings

addition

adder (written)

approximation

conversion rate

conversion table

conversion (e.g. yen to dollars)

addition

reckoning from some position (e.g. point, date, etc.)

counting backwards

pooling

non-electronic computer (i.e. person carrying out computation)

statement of account

inside the computer

slide rule

calculation

computer-tree

settlement of accounts

cost accounting

miscalculation

addition