What is 5-5x5+5?

Feek said:
I have maths A level and genuinely, the first time I ever heard of this bodmas thing was on these forums.
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I don't what to tell you, except that your education must have either been seriously lacking, or such a long time ago that you've forgotton! FWIW, I have a degree in maths, not that I need it for this level TBF!
 
Feek said:
I have maths A level and genuinely, the first time I ever heard of this bodmas thing was on these forums.
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How on earth do you get as far as A level maths without knowing that order of operations exists? It's something you're taught at KS3 (if not earlier?) these days.
 
Kenai said:
How on earth do you get as far as A level maths without knowing that order of operations exists? It's something you're taught at KS3 (if not earlier?) these days.
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Brackets. Everything was bracketed which is surely a lot more straightforward than this. Work out the bracketed values and then do the rest because it removes all the ambiguities.

JohnG7 said:
In UK (maths not math) it would probably have brackets around part of it and we were taught to do that part first in school during the 70-80's.
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As per this.
 
Feek said:
Brackets. Everything was bracketed which is surely a lot more straightforward than this. Work out the bracketed values and then do the rest because it removes all the ambiguities.
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Evidently this was a counter-productive way to teach people then, as order of operations isn't some new fangled thing. Sounds like you were taught to bracket everything because they couldn't be bothered to teach you the proper rules.
 
Feek said:
Brackets. Everything was bracketed which is surely a lot more straightforward than this. Work out the bracketed values and then do the rest because it removes all the ambiguities.
As per this.
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In fairness, this entire question and many other varients like it, is mostly about trolling people like yourself! As you say, brackets make it far more obvious. I would say that there isn't any ambiguity - there isn't, there's one right answer and any other answer is definitively wrong, but if you actually want to communicate effectively to a large audience, then there is a certain responsibility on the person setting the question to make it obvious. This question is solely designed to trip people up, and going by this thread, it seems to have worked!
 
5 But then I went to school in the 80's when we did proper maths. ;)

((5-5)x5)+5 = 5
 
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RxR said:
BOMDAS
Brackets then multiplication then division then addition then substraction.

So x first, and to get the multiplication do the 1st side on the left of it first. 5-5 =0
Then add the 5+5 to get the rhs of the multiplication - 5+5 =10
=
5-5 =(0) x 5 +5 (10)
= 0 x 10 = 0.
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NO!
 
Partial equations with custom precedence bootstrapping - is the nets new form of trivia?

We could give them a run for their money with obscure logic formulas.
 
Feek said:
I was never taught bodmas, it was all about brackets.

So I look at it this way.

5-5x5+5

I start with five peas.

I take away five peas, that gives me no peas.

I multiply those no peas by five, I still have no peas.

Then I add five peas.

I end up with five peas.

Now can someone explain to me in simple terms how the answer can be anything different?
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Because operations have different precedence, this has been true whether you learned some acronym like "BODMAS" at school or not.

Multiplication and division have higher precedence over addition and subtraction. These operators are right-associative too meaning you work from left to right...

So...

you have 5 * 5 which gives you 25 (multiplication ahead of addition and subtraction)

5 - 25 gives you -20 (working left to right)

and adding 5 gives you 15
 
Feek said:
I have maths A level and genuinely, the first time I ever heard of this bodmas thing was on these forums.
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You don't need it for proper maths. It's intentionally ambiguous to provoke arguments on facebook and get post interaction level up.
 
RxR said:
Partial equations with custom precedence bootstrapping - is the nets new form of trivia?

We could give them a run for their money with obscure logic formulas.
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No, nothing like that. Just people not understanding bodmas. Its not weird or obscure and there's only one possible answer.
 
dowie said:
Because operations have different precedence, this has been true whether you learned some acronym like "BODMAS" at school or not.
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There was no acronym, it was all about stuff being properly bracketed, as I’ve already explained. That way, anyone can follow it.
 
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