Calendar reasoning — Given that Monday falls on 20 March 1995, determine the day of the week on 3 November 1994 (use the given anchor date, not real-world memory).

Difficulty: Medium

Correct Answer: Thursday

Explanation:


Introduction / Context:
Calendar questions often provide one “anchor” date and ask you to deduce the day on another date. The skill is to convert dates to an offset in days and then take that offset modulo 7 to map back to a weekday.


Given Data / Assumptions:

  • Anchor: 20 March 1995 is a Monday (given).
  • Target: 3 November 1994 (earlier date).
  • Weekdays repeat every 7 days.


Concept / Approach:
When moving from the anchor to another date, count the exact number of days between the dates, then shift the weekday by (difference mod 7). A negative shift just means “go backward.”


Step-by-Step Solution:

1) Count days from 3 Nov 1994 to 20 Mar 1995.2) From 3 Nov 1994 to 30 Nov 1994 = 27 days.3) Dec 1994 = 31, Jan 1995 = 31, Feb 1995 = 28 (1995 is not leap), total so far 27+31+31+28 = 117.4) Add 1–20 Mar 1995 = 20; grand total = 137 days.5) 137 mod 7 = 4 (since 7×19 = 133).6) If 20 Mar 1995 is Monday, then 4 days earlier is Thursday.


Verification / Alternative check:
Working forward: 3 Nov 1994 → add 137 days → Monday implies the start was Monday − 4 = Thursday. Same result.


Why Other Options Are Wrong:

  • Tuesday/Sunday: These correspond to different remainders mod 7 and do not match the computed offset.
  • None of these: A valid weekday (Thursday) matches.


Common Pitfalls:

  • Forgetting that 1995 is not a leap year.
  • Counting 3 Nov inclusively or exclusively inconsistently; keep a consistent convention.


Final Answer:
Thursday

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