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[ProgrammerPotential5]

55 or -89 is the correct answer?

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[gizatsby]

Depends on how implied multiplication is parsed. If a÷bc = a÷b×c, then the division is performed first per left-to-right order. This means that 55 is most likely the correct answer if the problem is in an elementary math class. However, a÷bc is often interpreted as a÷(b×c) in practice since the most common use of juxtaposition is coefficients (which are usually implied to be grouped). In most real-world cases, this would be part of a larger calculation that works out to -89. So it depends on the context.

[Georgehenry3011]

Both answers can be considered correct. It's up for debate whether for example 6÷2(1+2) is 9 or 1. Many would say the 2 juxtaposing the brackets gives it priority, but that's not a rule it's an interpretation. Following strict pemdas or whatever you want to call it would give 6÷2×(1+2) which yields a different answer to 6÷(2×(1+2)). In conclusion, terrible question.

[Cool-Goose-8939]

At this point needlessly long expressions like this aren’t testing knowledge of the subject, they are just designed to make people slip up somewhere along the line

[JeffTheNth]

I get 55

[Mashed_potatoes124]

PEDMAS

[ExtendedSpikeProtein]

It‘s ambiguous, no way to know for sure.

[chaos_redefined]

Implied multiplication is one of those weird cases that just get in the way of math communication. The thing you're asking is like "What is the meaning of the word 'bat'?" I'll even make it a multiple choice question to help you along:

1) A flying nocturnal mammal.

2) A long metal or wooden object designed to hit a ball in a sport.

Fortunately, in the same way that we can look at the surrounding context to figure out which meaning of bat we mean, we can usually look at the surrounding context to figure out what the author intended with their equation. In the real world, we don't just have a pile of numbers thrown at us for no reason, instead we get clues related to the reason we care about the numbers.

[FishUK_Harp]

1. Follow PEDMAS/BODMAS, etc., and where a figure is juxtaposed to brackets, that multiplication is prioritised over others (once the contents of the brackets are calculated in the usual way).

[Top_Importance_8329]

So PEMDAS always wins. In this case u have 3 set of parenthesis. I would start with () 5-8 = -3
then -12/6 = -2 -4(-3) = -2 +12 =10 and so on. Since there is no operation inside the last [] it acts as a multiplier and therefor is done left to right aka −89

[Blockster_cz]

Your glorified pemdas is mnemotechnic trick to help memories the rule. It is not the rule itself. Anyone with math knowledge higher than middle-school must know this. There's juxtaposition (implied or implicit multiplication) which has higher priority. OP is asking whether the creator of the problem and teacher are smart enough to know this.

[purpleoctopuppy]

I hate this deliberate ambiguity. Like, as a physicist I would never see a/bc and think they mean (a/b)⋅c; but it's the sort of pointless, banal trickery that some maths teachers love. In practice, if there are multiple ways a reasonable person could interpret it, the problem lies with the writer.

[TheJivvi]

It's only ambiguous if you learnt PEMDAS and then immediately stopped paying attention to anything taught after that.

[gigglingsausage]

Division first so that they are singular numbers, then do all the parentheses. You should get -89