2012 January 1st is Sunday , then which day is the independence day of the…

Key insight: count how many days pass from January 1 to August 15, then take that total mod 7 to find how many weekdays to move forward from Sunday.

• 2012 is a leap year, so February has 29 days.

• Count days after January 1 up to August 15:

  30 (rest of Jan) + 29 (Feb) + 31 (Mar) + 30 (Apr) + 31 (May) + 30 (Jun) + 31 (Jul) + 15 (Aug) = 227

• Compute the weekday shift: 227 ÷ 7 = 32 weeks with remainder 3, so move forward 3 days from Sunday.

Starting from Sunday, moving forward 3 days gives Wednesday.

Therefore the independence day (August 15, 2012) is Wednesday.