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How Many Days?

Age 5 to 7
Challenge Level Yellow star
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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."


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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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