The answer hasn't been posted, but I know I got it wrong. And I know why. I should have remembered that course I did in 1986.5 + 5 + 5  5 + 5 + 5  5 + 5 x 0 = ?
Maths brainteaser.
 bindeweede
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Maths brainteaser.
Found on Facebook.
Re: Maths brainteaser.
bindeweede wrote:Found on Facebook.
The answer hasn't been posted, but I know I got it wrong. And I know why. I should have remembered that course I did in 1986.5 + 5 + 5  5 + 5 + 5  5 + 5 x 0 = ?
I would think there are number of possible answers depending on how you group the operations...however that x0 at the end suggests that the answer will be 0...if I've remembered the conventions correctly.
 bindeweede
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Re: Maths brainteaser.
panama wrote:bindeweede wrote:Found on Facebook.
The answer hasn't been posted, but I know I got it wrong. And I know why. I should have remembered that course I did in 1986.5 + 5 + 5  5 + 5 + 5  5 + 5 x 0 = ?
I would think there are number of possible answers depending on how you group the operations...however that x0 at the end suggests that the answer will be 0...if I've remembered the conventions correctly.
Well, I answered 0, but then I remembered something about some operations having a sort of priority over others. I won't spoil it for now.
Re: Maths brainteaser.
I'm pretty sure you do the multiplication first and then simply add up the rest making 10.
Don't blame me  I voted remain
 bindeweede
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Re: Maths brainteaser.
Are you sure, chaggle? 56,000 people have what I think is the right answer, and it isn't 10
Re: Maths brainteaser.
I'd say 15 ... I made it 20 to begin with, but I think the final 5 is the only one (given that there aren't any brackets) that is multiplied by zero.
Re: Maths brainteaser.
Sorry  I meant 15.bindeweede wrote:Are you sure, chaggle? 56,000 people have what I think is the right answer, and it isn't 10
Don't blame me  I voted remain

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Re: Maths brainteaser.
I would have said 0 too, unless it were written: 5 + 5 + 5  5 + 5 + 5  5 + [5 x 0] = 15

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Re: Maths brainteaser.
Yes. The way I was taught at school it is 0 unless you insert the brackets as you suggest.Silentecho wrote:I would have said 0 too, unless it were written: 5 + 5 + 5  5 + 5 + 5  5 + [5 x 0] = 15
I don't accept that 0 is wrong, only, perhaps, that there are different conventions for working it out that will give different answers.
thIS sIGnaTure iS an
Re: Maths brainteaser.
Croydon13013 wrote:Yes. The way I was taught at school it is 0 unless you insert the brackets as you suggest.Silentecho wrote:I would have said 0 too, unless it were written: 5 + 5 + 5  5 + 5 + 5  5 + [5 x 0] = 15
I don't accept that 0 is wrong, only, perhaps, that there are different conventions for working it out that will give different answers.
Ditto.
(Though I am notoriously crap at maths)
Re: Maths brainteaser.
15 is the answer apparently. Here's a Wikipedia article on the subject http://en.wikipedia.org/wiki/Order_of_operations
n mathematics and computer programming, the order of operations (sometimes called operator precedence) is a rule used to clarify unambiguously which procedures should be performed first in a given mathematical expression.
For example, in mathematics and most computer languages multiplication is done before addition; in the expression 2 + 3 × 4, the answer is 14. Brackets, which have their own rules, may be used to avoid confusion, thus the preceding expression may also be rendered 2 + (3 × 4), but the brackets are not required as multiplication still has precedence without them.
Re: Maths brainteaser.
Me being wrong about arithmetic would in no way be strange......panama wrote:15 is the answer apparently. Here's a Wikipedia article on the subject http://en.wikipedia.org/wiki/Order_of_operations
n mathematics and computer programming, the order of operations (sometimes called operator precedence) is a rule used to clarify unambiguously which procedures should be performed first in a given mathematical expression.
For example, in mathematics and most computer languages multiplication is done before addition; in the expression 2 + 3 × 4, the answer is 14. Brackets, which have their own rules, may be used to avoid confusion, thus the preceding expression may also be rendered 2 + (3 × 4), but the brackets are not required as multiplication still has precedence without them.
:(
 bindeweede
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Re: Maths brainteaser.
If you use a simple calculator, the answer comes up as "0", but if you use something like a spreadsheet, which has all sorts of mathematical functions built in, it comes up with "15".panama wrote:15 is the answer apparently. Here's a Wikipedia article on the subject http://en.wikipedia.org/wiki/Order_of_operations

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Re: Maths brainteaser.
Yes.bimbow wrote: If you use a simple calculator, the answer comes up as "0", but if you use something like a spreadsheet, which has all sorts of mathematical functions built in, it comes up with "15".
So did the convention change at some point or are a number of us misremembering what we were taught?
The left to right method used by my calculator, and various of us, still seems more logical to me. Although when both Wikipedia and my Excel spreadsheet are ganging up on me I have to admit that I must be wrong.
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Re: Maths brainteaser.
The longstanding convention is X & / first, then + & . Zero is wrong, the answer is definitely 15.