Because OCT 31=DEC 25
Because OCT 31 == DEC 25
Because Dec 25 = Oct 31
The mathematician says "2" The Physicist says "2, plus or minus 0.1" The engineer says "Probably around 2, but let's say 3 to be on the safe side".
Don't worry they'll tell you.
Because OCT 31 is the same as DEC 25.
Because Oct 31 is Dec 25
Because oct 31 = dec 25
Because 31 OCT = 25 DEC.