Quick Method: Odd Days Calculation
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Count odd days from 2000 to 2009
- 2000 (leap year) → 2 odd days
- 2001 to 2009 (8 normal years + 1 leap year) → (8 × 1) + (1 × 2) = 10 odd days
- Total odd days from 2000 to 2009 = (2 + 10) = 12 → 12 mod 7 = 5 odd days
- 2009 ended on a Thursday (Base day: Thursday)
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Count odd days from Jan to Aug 15, 2010
- Jan (31) → 3 odd days
- Feb (28) → 0 odd days
- Mar (31) → 3 odd days
- Apr (30) → 2 odd days
- May (31) → 3 odd days
- Jun (30) → 2 odd days
- Jul (31) → 3 odd days
- Aug 1-15 (15 days) → 1 odd day
- Total odd days = 3 + 0 + 3 + 2 + 3 + 2 + 3 + 1 = 17 → 17 mod 7 = 3 odd days
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Final Calculation
- Thursday + 3 odd days = Sunday
Answer: 15th August 2010 was a Sunday. ✅
examcare Answered question February 13, 2025