If the 9th of a month is 2 days earlier than Saturday, what day will be on the 26th of that month.
2 days earlier than Saturday will be Thursday. So day 9 of that month is Thursday. Number of days between 26 and 9 is 17. Since 17 = 2 X 7 + 3, so excess days are 3. So we can count the day to Sunday.