arithmetic - the branch of pure mathematics dealing with the theory of numerical calculations

compute, calculate, cipher, cypher, figure, reckon, work out - make a mathematical calculation or computation

keep, hold on - retain possession of; "Can I keep my old stuffed animals?"; "She kept her maiden name after she married"

dock - deduct from someone's wages

logical system, system of logic, logic - a system of reasoning

extrapolate - gain knowledge of (an area not known or experienced) by extrapolating

conclude, reason, reason out - decide by reasoning; draw or come to a conclusion; "We reasoned that it was cheaper to rent than to buy a house"

carry back - deduct a loss or an unused credit from taxable income for a prior period

surmise - infer from incomplete evidence

elicit - derive by reason; "elicit a solution"