Calendar and Day Calculations

Using January 1, 1900 (Monday) as an anchor, there are 74 years and 18 leap years up to 1974, resulting in 92 odd days (or 1 odd day). Thus, January 1, 1974 was a Tuesday. Adding 318 elapsed days to November 15 (318 modulo 7 is 3) shifts Tuesday by 3 days to Friday.

From January 1, 2007 (Monday) to January 1, 2009, there are 2 years, including the leap year 2008. This adds a total of 3 odd days (2 standard + 1 leap day). Moving 3 days forward from Monday gives Thursday. Other options represent incorrect weekday offsets.

From January 1, 2007 to January 1, 2011, there are 4 years. This interval includes one leap year (2008), contributing 5 total odd days (4 standard + 1 leap day). Adding 5 days to Monday results in Saturday. Distractors represent other days of the week.

Divide 61 by 7 to find the number of full weeks and the remainder. 61 divided by 7 is 8 with a remainder of 5. Counting 5 days forward from Monday (Tuesday, Wednesday, Thursday, Friday, Saturday) results in Saturday.

The year 2052 is a leap year. Calculating from a known anchor like January 1, 2026 (Thursday), the 26-year difference includes 6 leap days (in 2028, 2032, 2036, 2040, 2044, 2048), resulting in 32 odd days. Since 32 modulo 7 is 4, adding 4 days to Thursday yields Monday.