Comment on A fake Facebook event disguised as a math problem has been one of its top posts for 6 months
SmartmanApps@programming.dev 4 days agoI fully agree that if it comes down to “left to right”
It never does
But I’ve just shown why that “rule” is a common part
No you didn’t. You showed you didn’t understand the rules. Doing addition first for 10-1+1 is 10+1-1, not 10-(1+1). It literally means add all positive numbers together first, which are +10 and +1, as per Maths textbooks…
Note in the above simplification of the coefficients we have 6-11+5-7+2=6+5+2-11-7=13-18=-5, and not, as you claim 6-(11+5)-(7+2)=6-16-9=-19
because it is so weird and quite esoteric
It’s a convention, not a rule, and as such can be completely ignored by those who understand the rules. See literal textbook example
HereIAm@lemmy.world 4 days ago
I know it’s not a rule, hence why I put it in quotation marks. I noted in another comment that, yes, the proper way is to group it as 1+(-2)+3 and you can do it in any order. What I meant with ““rule”” is the meme questions pray on people not understanding/remembering what the actual rules are or why “left to right” conventions exist.
SmartmanApps@programming.dev 3 days ago
No it isn’t.
You can do it in any order anyway
left to right 1-2+3=-1+3=2
addition first 1+3-2=4-2=2
subtraction first -2+1+3=-1+3=2
right to left 3-2+1=1+1=2
And you showed that you were one of them. Every answer you got other than 4 was wrong, because you didn’t understand the rules. spoiler alert: doing it in different orders never means add brackets to it. Addition first for 10-1+1 is 10+1-1, not 10-(1+1). See previous textbook example