SSC CHSL Model Paper 20

The year 2012 is a leap year so it has 2 odd days.
The year 2011 is an ordinary year, so it has 1 odd day.
Therefore total odd days = 2 + 1 = 3
So, the day on 8th January 2013 will be 3 days beyond the day on 8th January 2011.
8th January 2011 is Wednesday.