
Method:
Example: Find the missing operand: 12 ? 8 = 20 Here the result 20 is a number that is greater than the 12 and 8. Therefore the operand is addition. Answer: + Example: 12 ? 3 = 9 Here the result is a number less the number on the left side of the operand, it is subtraction. Answer:  Example: 12 ? 12 = 0 Here the result is 0, therefore the operand is subtraction. Answer:  Example: 12 ? 0 = 12 If the result is equal to the number on the left side of the operand, it is addition. Answer: + Directions: Answer the following questions. Also write at least ten examples of your own. 