user: Question: What period was there a career average of 48.15?
Columns: ['Rank', 'Average', 'Player', 'Runs', 'Innings', 'Not Out', 'Period']
Types: ['real', 'text', 'text', 'real', 'real', 'real', 'text']
Sample row: [1.0, '56.85', 'George Bailey', 1535.0, 33.0, 4.0, '2012-']
SQL:

assistant: SELECT "Period" FROM "Table" WHERE "Average" = '48.15';