Table: wolverines_1903_football_stats_3
Columns: player
position
starter
touchdowns
extra_points
field_goals
points

Question: What is the average number of field goals scored by a right halfback who had more than 3 touchdowns?
SQL: SELECT AVG("field_goals") FROM wolverines_1903_football_stats_3 WHERE "position" = 'right halfback' AND "touchdowns" > 3