[ruoflaw]

your 50 per cent part.

[Strategerist]

It's not ABSOLUTELY precise.

But three days on either side of a Full moon is 7 days (including the day itself)...add that to a New Moon, and 14 days each lunar cycle are within three days of a Full or New Moon.

I stand horribly guilty of saying 50% when I should have said 46.66666666666666666666666666666666666666% of a calendar month is within 3 days of a New or Full Moon.