India's Constitution came into force on 26 January 1950. Using odd days, find the day of the week of that date.

Explanation

1. 01

   Complete years before $1950 = 1949$. The first 1600 years give 0 odd days; the next 300 years give 1.

2. 02

   The remaining 49 years (1901–1949) have 12 leap years and 37 ordinary years: $12 \times 2 + 37 = 61$ odd days, and $61 = 8 \times 7 + 5$ gives 5.

3. 03

   26 days of January 1950 give $26 = 3 \times 7 + 5$, that is 5 odd days.

4. 04

   Total $1 + 5 + 5 = 11$, and $11 - 7 = 4$. With 0 = Sunday, 4 = Thursday.