Aptitude - Calendar - Discussion

How you found 1600 years and 400 years separately?

Please took 19/08/2015 & explain?

19.8.2015 was a wednesday.

Solution:

I. Take the year part and split it into two parts (ie) 2014 & 2015
II. 2014 ...... Can be splited into 2000 years and 14 years.
III. Odd days calculation: since 2000 is a leap century (2000/400 =50) year so 0 odd day.
...>(14 /4= quotient =3 ,remaider=2) gives;

Leap year =3 . Ordinary year =(14-3=11) 11.
.....>Odd days in 14 yrs= [(3*2=6)+(11*1=11)]=6+11=17
Therfore total no of odd days in 2014= 17.
IV. 19.8.2015

Odd days:
Jan Feb Mar Apr May Jun July Aug
31 28 31 30 31 30 31 19
Add all days= 231,
Therfore odd days upto 19.8.2015 = 231,
V.Total odd days = 17(from step III) + 231(from step IV).
=248 /7 = 3(Remainder =3, And quotient =35).

0 -sunday
1- monday
2- tuesday
3- wednesday
4- thursday
5- friday
6- saturday

Therfore answer is Wednesday.

Notes:
Century leap years =400 , 800,1200,1600 ,2000,2400. That is a year which is divisible by 400.
100 is not a leap year eventhough it is divisible 4. Centuary year should be divisible by 400.

Why 1600 and 400?

Because 1200 is min leap year 1300 in not leap year same 1400, 1500 also not a leap year 1600 is a leap year and the max leap year is 2000. Therefore all problems we get 1600.

Here, 2001 = 1600 + 400 (1600 is leap year so 0 odd day & 400 is also leap year therefore 0 odd days).

I think 4th April, 2001 comes to be Friday. So the correct answer will be 2nd April series.

Without taking any base day how would I say 0 = Sunday?

Why is 1st day of April taken in consideration? please explain.

Because particular day of April was not given so we have to check out that the April 2001 starts from which day of the week?

Here, present year 2001.

But we take a number of completed years.

Here just know the week on that data we have to choose Wednesday and +7 next repeated.

I hope you understand.
.

Can I know why there is a need of odd days in years 1600, 400?