Synonyms for Addition, Subtraction, Multiplication, Division, and equals.

Addition-
-Increasing
-Plus
-Add
-Total
-Gain

Multiplication-
-Times
-By
-Product
-Of
-Multiply

Subtraction-
-Take Away
-Subtract
-Minus
-Deduct
-Less

Division-
-Goes Into
-Divide
-Quotient
-How Many Times
-Parting

Equals-
-Is
-Answer
-Product
-Sum
-Difference