Aptitude - Calendar - Discussion

Leap year is any year divisible by four. How is hundred not a leap year!!!

The earth takes 365.24 days to take one revolution about sun. So after 4 year a correction of 1 day is taken for extra 0.98 day.

And to correct an error of 0.02 day 100th year is not taken as leap year. After a Century that error is a full day long, so we skip the leap year.

This is easy to understand when you realize the difference between 365.25 and 365.24 is 1/100 of a day per year. So after 100 years we have accumulated a full day of error.

Why is it the 100 years have 5 odd days ?

100 years has 5 odd days. so the 101st year must only start with Friday, right? for example if a non leap year has 1 odd day, then it starts with the next day when you are comparing with the previous year. so I think the last day of the first Century must be 'Thursday' and second century is 'Tuesday' and so on.

How we know that 100 years has 24 leap year and 76 ordinary year?

Because every 4th year is a leap year.

Please tells me which day you considered as first day of century whether Sunday or Monday?

Every 4th year may not be a leap year because the year which is divisible by 100 then that year is know as leap year or leap centenary.

If 01.01.0001 is a Sunday then the last day of the century i.e. 31.12.0001 would be Thursday (A century has 5 odd days).

01.01.0101 would be Friday and the last day of this century year would be Tuesday.

01.01.0201 would be Wednesday and last day of this century would be Sunday.

01.01.0301 would be Monday and last day of this century i.e. 31.01.0400 would be a Saturday.

Again 01.01.0401 would be a Sunday.

Thus we see that the last day of century years are Tuesday or Thursday or or Saturday or Sunday.

Please correct me if my calculation is wrong.

It's so simple. 100/7=14 and remainder is 2. So,

0=Sunday.
1=Monday.
2=Tuesday.

So it cannot be Tuesday (2).