5 Saturdays, 5 Sundays, and 5 Mondays

December 2012 has 5 Saturdays,  5 Sundays and 5 Mondays and although you  may have heard this only happens every 823 years, I would urge you to do the math or look at a calendar before buying into this hoax. This will happen again in December 2018 and many more times in other months when the month has 31 days in it. However, it's a great trivia question to use on your friends. And, for a little calendar math, here's how you calculate the number of days for a loan period.