Table schema:
CREATE TABLE table_25042332_16 (below_50_percentage_of_median_income VARCHAR, below_40_percentage_of_median_income VARCHAR)

Question: What percentage of the population is below 50% of the median income in the region where 10.4% of the population earns below 40% of the median income?
SQL: SELECT COUNT(below_50_percentage_of_median_income) FROM table_25042332_16 WHERE below_40_percentage_of_median_income = "10.4%"