Download our Android app to get updates on your mobile

Important Formulas - Calendar - Tricks & Shortcuts

1. Odd Days:
We are supposed to find the day of the week on a given date.
For this, we use the concept of 'odd days'.
In a given period, the number of days more than the complete weeks are called odd days.

2. Leap Year:
(i). Every year divisible by 4 is a leap year, if it is not a century.
(ii). Every 4th century is a leap year and no other century is a leap year.
Note: A leap year has 366 days.
Examples:
i.  Each of the years 1948, 2004, 1676 etc. is a leap year.
ii.  Each of the years 400, 800, 1200, 1600, 2000 etc. is a leap year.
iii. None of the years 2001, 2002, 2003, 2005, 1800, 2100 is a leap year.


3.  Ordinary Year:
The year which is not a leap year is called an ordinary years. An ordinary year has 365 days.


4. Counting of Odd Days:
   1. 1 ordinary year = 365 days = (52 weeks + 1 day.)
            Therefore 1 ordinary year has 1 odd day.
       2.     1 leap year = 366 days = (52 weeks + 2 days)
               Therefore 1 leap year has 2 odd days.
       3.     100 years = 76 ordinary years + 24 leap years
                 = (76 x 1 + 24 x 2) odd days = 124 odd days.
                 = (17 weeks + days) ≡  5 odd days.
                      Therefore Number of odd days in 100 years = 5.
               Number of odd days in 200 years = (5 x 2) ≡ 3 odd days.
               Number of odd days in 300 years = (5 x 3) ≡ 1 odd day.
               Number of odd days in 400 years = (5 x 4 + 1) ≡ 0 odd day.
               Similarly, each one of 800 years, 1200 years, 1600 years, 2000 years etc. has 0 odd days.


5.    Day of the Week Related to Odd Days:
No. of days:
0
1
2
3
4
5
6
Day:
Sun.
Mon.
Tues.
Wed.
Thurs.
Fri.
Sat.



Quantitative Aptitude Quizzes and Study Material

Click here for Quantitative Aptitude & Data Interpretation Topics & Formulas
Important Formulas - Calendar - Tricks & Shortcuts Important Formulas - Calendar - Tricks & Shortcuts Reviewed by Job today on 16:14 Rating: 5

No comments:

Powered by Blogger.