CREATE TABLE table_24222929_3 (original_airdate VARCHAR2, live VARCHAR2, sd_total_viewers VARCHAR2)

When did the episode that had 3.69 million total viewers (Live and SD types combined) first air?
SELECT original_airdate FROM table_24222929_3 WHERE live + sd_total_viewers = "3.69 million"
SELECT "original_airdate" FROM "table_24222929_3" WHERE "3.69 million" = "live" + "sd_total_viewers"