CALENDAR.

Dear student

Go through these the 10 bullet points to solve questions on calender.

1. 1st January 0001 was a Monday.

2. Calendar repeats after every 400 years.

3. Leap year- it is always divisible by 4, but century years are not leap years unless they are divisible by 400.

4. Odd days- remainder obtained when no. of days is divided by 7. Normal year has 1 odd day and leap year has 2 odd days.

5. Calendar moves ahead by number of odd days.

6. While checking leap year just analyze whether February falls in that period or not.

7. Century has 5 odd days and leap century has 6 odd days.

8. Take out net odd days.( add all the odd days and again divide by 7)

9. In a normal year 1st January and 2nd July and 1st October fall on the same day. In a leap year 1st January 1st July and 30th September fall on the same day.

10. 1st January 1901 was Tuesday.

We calculate odd days on the basis of the previous month.

Example – what day is it on 29th August 1982?

Method- As we know 1/1/1901 was a Tuesday now we take 1982 and 1901 - 1982-1901=81 years. - 81/4=20…. ( disregard decimal) - 81+20=101 - 101/7- remainder is 3, so 3 days from Tuesday is Friday. -Now check whether it is a leap year or not. In this case it is not a leap year. Therefore 2nd July will be Friday - Now we have to go month wise . 2nd august = 3odd days= so from Friday 3 odd days will be Monday so 29th August will be a Sunday.