Examkin

Soru

Zorluk: KolayClocks and Calendars

If 1st January 2004 was a Thursday, what day of the week was 1st January 2005?

Cevap: Saturday / saturday

Cevap

Saturday
The correct answer is Saturday. The year 2004 is a leap year containing 366 days. Since the time period from 1st January 2004 to 1st January 2005 includes February 29th, there are 2 odd days. Advancing 2 days from Thursday results in Saturday.

Adım Adım Çözüm

1
Determine if the year 2004 is a leap year.
2004 is divisible by 4, so it is a leap year containing 366 days.
Leap years include an extra day (29th February).
2
Calculate the number of odd days between 1st January 2004 and 1st January 2005.
366 days divided by 7 equals 52 weeks and 2 odd days (366(mod7)=2366 \pmod 7 = 2).
Full weeks do not change the day of the week, so only the remainder (odd days) shifts the day.
3
Advance the given day by the number of odd days.
Thursday + 2 days = Saturday.
Adding 2 odd days to Thursday moves the day forward to Saturday.

Anahtar Kavram

Calculating day of the week shifts across leap years using odd days
Bu soruyu puanla

Konular

Clocks and Calendars

Bu konudan daha fazla soru