April 10th is the 100th day of this year (2009). During leap years, however, the 100th day of those years will occur on April 9th. This type of information is obtained by consulting a Julian calendar - a calendar that shows, besides normal information, the number of days which have elapsed (and usually also how many are remaining) in the current year.
One hundredth of a century is a year.
If you want that sort of precision then you need to specify whether you want the number of days in a solar year, a siderial year, a synodic year, a tropical year.
century centenary centennial
The answer depends on when school started, how many holidays, how many teacher training (INSET in UK) days.
the 4 is the hundredth
The one hundredth day of a non-leap year is April 10.
The two hundredth day of a leap year is July 18.
The 10th of April in an ordinary year and the 9th of April in a leap year.
One hundredth of a century is a year.
homework for day 101
If you want that sort of precision then you need to specify whether you want the number of days in a solar year, a siderial year, a synodic year, a tropical year.
The 10th of April in a normal year and the 9th of April in a leap year.
April 20th
a century
1900 is the last year (the hundredth year) of the 19th century.
one hundredth 1/100
Century, centennial, centenary