6 - 2 x 4 + 3

Ok so if I use BIDMAS (Brackets Indices Division Multiplication Addition and Subtraction) I get

= 6 - 8 + 3

= 6 - 11

= -5

I was then told the answer was 1 which you get by doing

= 6 - 8 + 3

= -2 + 3

= 1

How come when using BIDMAS rule, which all children use at school in the UK, this calculation does not work if the answer is really 1. Can anyone explain to me simply... very simply. Thanks