Aptitude - Calendar - Discussion

There's a better way to solve this:

We know that for 2000 years, the number of odd days is 0.
Consider 17 June, 2001.

for the previous 2000 years, there are 0 odd days.
for the year of 2001, starting from Jan
31+28+31+30+31+17 = 168

which means there are 0 odd days.

now the day of the week for 17 June 2001 is Sunday.

now we need the day for 17 June 1998. Simply subtract the odd days of the preceding three years.

2000 is a leap year, whereas 1999 and 1998 are ordinary years.

So 0 - 2 - 1 - 1 = -4.

Go back 4 days from Sunday and you get Wednesday.

Why it's needed to calculate odd days for 1600 and 300?

How to calculate ordinary year and leap years in one century?

Please explain?

Simple , leap year = 100 / 4 = 25.
Ordinary year = 100 - 25 = 75.

If you want to find number of odd days in 100 years, then 100/4=25.(Only. Quotient) Now,( 100 +25)/7=6(remainder).
So, there are 6 odd days in 100 no of Years.

How many odd days in between 1901 to 2000? Please tell me the answer with the explanation.

In 1998.

i.e, 98 is a leap year so you should have to consider 29 days in Feb month but you hadn't considered it.

Can anybody derive and say 15th June 1998 is what day? Please

How to calculate 1 odd day in 300years?

Thanks @Sri Harsha.