user: Question: What is the percentage democrats with democratic plurality of -3, and 2/5 democrat/republican?
Columns: ['State ranked in partisan order', 'Percentage Democrats', 'Percentage Republicans', 'Democratic/ Republican', 'Democratic seat plurality']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Massachusetts', '100%', '0%', '10/0', '10']
SQL:

assistant: SELECT "Percentage Democrats" FROM "Table" WHERE "Democratic seat plurality" = '-3' AND "Democratic/ Republican" = '2/5';