"Viral" maths problem
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"Viral" maths problem
I saw this come up on Facebook a day or so ago from The Mirror, so I thought I'd post it here. It's nothing original  I've seen similar before. It's also here.
What is 6 ÷ 2(1+2) ?
I'll be back to discuss.
What is 6 ÷ 2(1+2) ?
I'll be back to discuss.
 Johnny Canuck
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Re: "Viral" maths problem
Nine. Simple BEDMAS: do the bracket to get 6/2*3, then multiplication and division left to right. This is objectively the only answer.
Q: What is the longest word in the world?
A: "Gigaparsecs", because there is a gigaparsec before the last S.
A: "Gigaparsecs", because there is a gigaparsec before the last S.
 Matt Morrison
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Re: "Viral" maths problem
If a(b+c) == ab + ac isn't it 1?
Not done maths in many years so don't remember the rules as to when you would expand the brackets.
Not done maths in many years so don't remember the rules as to when you would expand the brackets.

 Postapocalypse
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Re: "Viral" maths problem
If you read the explanation in the second link I gave or watch this video, they're quite clear that the answer is 9.
However, I think to talk about it simply in terms of BEDMAS/BODMAS/BIDMAS/TISWAS is to miss the point about where the confusion or potential ambiguity lies. And the website and video do not address this.
We have 6 ÷ 2(1+2). If it was written as 6 ÷ 2 x (1+2) then pretty much everyone would agree that it is 9 and there would be no problem. The confusion comes from not putting the multiplication sign in leaving just 2(1+2) all stuck together because it looks like it is a term in the equation itself. Another example in the video is 1 ÷ 2y (even though as mentioned the video doesn't address the underlying source of confusion). Should that be taken as 1 / 2 * y, or 1 / (2y)?
The "correct" answer I suppose would just be whatever some committee of mathematical notation decides. It's not really a mathematical problem and talking of BEDMAS/BODMAS/BIDMAS/TISWAS does not resolve the problem either. But it is a poorly worded question and you'd never get anything written like that in "real life" outside a problem designed to deliberately confuse.
But aside fron the "correct" answer, we can still discuss what we think the aforementioned committee should reasonably decide. And I think if a number is put adjcent to the brackets like that with no multiplication sign then it's more reasonable to conclude that it goes with what's in the brackets so that they're treated as a single term. And that would make the answer 1. But because it's debatable and not everyone would agree, noone should ever write a formula like that.
However, I think to talk about it simply in terms of BEDMAS/BODMAS/BIDMAS/TISWAS is to miss the point about where the confusion or potential ambiguity lies. And the website and video do not address this.
We have 6 ÷ 2(1+2). If it was written as 6 ÷ 2 x (1+2) then pretty much everyone would agree that it is 9 and there would be no problem. The confusion comes from not putting the multiplication sign in leaving just 2(1+2) all stuck together because it looks like it is a term in the equation itself. Another example in the video is 1 ÷ 2y (even though as mentioned the video doesn't address the underlying source of confusion). Should that be taken as 1 / 2 * y, or 1 / (2y)?
The "correct" answer I suppose would just be whatever some committee of mathematical notation decides. It's not really a mathematical problem and talking of BEDMAS/BODMAS/BIDMAS/TISWAS does not resolve the problem either. But it is a poorly worded question and you'd never get anything written like that in "real life" outside a problem designed to deliberately confuse.
But aside fron the "correct" answer, we can still discuss what we think the aforementioned committee should reasonably decide. And I think if a number is put adjcent to the brackets like that with no multiplication sign then it's more reasonable to conclude that it goes with what's in the brackets so that they're treated as a single term. And that would make the answer 1. But because it's debatable and not everyone would agree, noone should ever write a formula like that.

 Acolyte
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Re: "Viral" maths problem
This is the only correct answer.Gavin Chipper wrote: ↑Mon Nov 16, 2020 12:45 pmBut because it's debatable and not everyone would agree, noone should ever write a formula like that.
 Ian Fitzpatrick
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Re: "Viral" maths problem
Totally agreeSam CapplemanLynes wrote: ↑Mon Nov 16, 2020 2:50 pmThis is the only correct answer.Gavin Chipper wrote: ↑Mon Nov 16, 2020 12:45 pmBut because it's debatable and not everyone would agree, noone should ever write a formula like that.
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 Johnny Canuck
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Re: "Viral" maths problem
Found a fellow programmer. Hello world.
Q: What is the longest word in the world?
A: "Gigaparsecs", because there is a gigaparsec before the last S.
A: "Gigaparsecs", because there is a gigaparsec before the last S.
 Matt Morrison
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Re: "Viral" maths problem
Code: Select all
const printThisShitOut = `Gevin is in love with ${c4c.filter(c => !!c.cool).join(" and ")} and he is a prick.`;
Re: "Viral" maths problem
Gevin's in love with himselfMatt Morrison wrote: ↑Fri Nov 20, 2020 11:45 pmCode: Select all
const printThisShitOut = `Gevin is in love with ${c4c.filter(c => !!c.cool).join(" and ")} and he is a prick.`;
<2m>

 Postapocalypse
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Re: "Viral" maths problem
Someone has to be.
 Matt Morrison
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Re: "Viral" maths problem
Damn I must've been drunk. Saw you quoting that and I thought I must've made that post years ago, not last night.
Re: "Viral" maths problem
Ha, me too  didn't notice the double notMatt Morrison wrote: ↑Sat Nov 21, 2020 1:24 pmDamn I must've been drunk. Saw you quoting that and I thought I must've made that post years ago, not last night.
<2m>
 Matt Morrison
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Re: "Viral" maths problem
I do like to work with booleans.
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