Stage: 1 Challenge Level: 
Deniz from IRMAK Primary and Secondary School, Turkey says, "We can't count February 25th and March 11th because it says 'between'.
From 26th day to the 29th day of February, (29th day included) there are 4 days. 2000 is a leap year - that's why February takes 29 days.
From 1st day to the 11th day of March (11th day excluded) there are 10 days. The sum of these numbers is 14 days."
Addition & subtraction. Mass and weight. Working systematically. Time. Calendars. Multiplication & division. Length/distance. Clock. Interactivities. Speed.
Published January 2000.
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