Why am I only just now realising that:
15 - 5 - 1 = 9
while:
15 - (5 - 1) = 11
When an expression has addition/subtraction as well as multiplication/division, I always understood the need for brackets around the +/- to prioritise them (#BODMAS). I just never realised it also changed the value of expressions that *only* use subtraction... 
#MathASongFilmOrTVShow
#HashtagGames
The Lord of the Operations - The Understanding of the Rules, The Two Powers and The Confusion on the Internet
@Hyphlosion
Yes, it's click-bait. Without context, or better still brackets or a solidus, the statement is ambiguous and either/both answers are equally valid/invalid.
#arithmetic #BODMAS #BOMDAS #PEMDAS #BEDMAS #BIDMAS
ѦਹѤʞ