How we find that about 36% of dates are the same in MMDDYY and DDMMYY
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1. There are 12 months in the year, so 12 of the possible month/day
combinations are ambiguous (if the day number is above 12, it is clear
which section is the day).
2. However, in one of those cases it actually doesn't matter which format is
used because the represented dates are identical (e.g., 01/01, 02/02).
Therefore, there are 11 days in each month on which there is the potential
for confusion.
3. There are 365.25 days/year (roughly).
4. Next we need the average number of days in a month so we can calculate what
percentage of those are ambiguous:
(365.25 days/year) / (12 months / year) = 30.4375 days/month
5. Finally, we calculate the proportion of ambiguous days to total average
days:
(11 days/month) / (30.4375 days/month) = .361396 (or approximately 36%)