csatmedium
If in a particular year 12th January is a Sunday, then which one of the following is correct?
- A.15th July is a Sunday if the year is a leap year.
- B.15th July is a Sunday if the year is not a leap year.
- C.12th July is a Sunday if the year is a leap year.
- D.12th July is not a Sunday if the year is a leap year.
▶ Answer & Explanation
Correct answer: C. 12th July is a Sunday if the year is a leap year.
To determine the day of the week for a future date, we count the total number of days between the given date and the target date and then find the remainder when divided by 7. The number of days between January 12 and July 12 in a leap year is 182. Since 182 is exactly divisible by 7 (182 = 26 * 7), July 12 will fall on the same day of the week as January 12. Therefore, if January 12 is a Sunday, July 12 will also be a Sunday in a leap year.
Source: UPSC csat 2020