If 31 January 2022 was a Monday, what was the day on the same date 100 years ago?

Tuesday

Using Code Method :-

\(\frac{Date+Month code+Year code+Last 2 digits of yr+Leap yrs till given yr}{7}\)

( Note: Remainder of the above sum will be the code of week day }

31 Jan 2022;

31 + 01 + 06 + 22 + 05 = 65

remainder of \(\frac{65}{7}\) = 02

Therefore, the code of 02 is Monday

Similarly,

31 Jan 1922;          ( Same date 100 yrs ago of 2022 )

31 + 01 + 0 + 22 + 05 = 59 

remainder of \(\frac{59}{7}\) = 03

Therefore, the code of 03 is Tuesday