Final answer:
The correct Oregon addition for these items is $300, representing the difference between the reported Oregon lottery winnings ($500) and the Oregon lottery losses ($200) claimed as a federal deduction.
Step-by-step explanation:
The Oregon addition for these items would be the total amount of the gambling losses deducted on the federal return that are attributed to gambling activities within Oregon. In this case, the taxpayer reports a deduction of $200 for Oregon lottery losses. Since the taxpayer is reporting $500 from Oregon lottery winnings, the Oregon addition will be the difference between the winnings and the losses reported for the Oregon lottery, which is $500 - $200 = $300. The correct answer is therefore $300.