DAY 13

Comment

29 February occurs only in leap years. 1904 was a leap year, as was 1908, 1912, ... and 1992. How many leap years is this?
Or, Winfred's 4th birthday was a leap year, as was her 8th, 12th, ... and 88th. How many birthdays is this?

Answer

23 (if you include 1904, the year Winifred was born).
22 (if you do not include 1904)

Readers' methods

Garth Scott:
90 divided by 4 = 22.5,
so 22 birthdays.

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