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Admin
02-11-2013, 10:44
Please use the poll to answer this math question. Votes are private so no embarrassment :)

Please DO NOT explain your answer as that will spoil this.

7 - 4 + 3 x 0 + 1 =

rugbyken
02-11-2013, 11:37
took the calculator to show me what i was doing wrong gonna have to burn my maths gcse now

Admin
03-11-2013, 07:57
OK

The correct answer is: 4


Order of operations, BODMAS




B

Brackets first


O

Orders (ie Powers and Square Roots, etc.)


DM

Division and Multiplication (left-to-right)


AS

Addition and Subtraction (left-to-right)





7 - 4 + 3 x 0 + 1 =

You do 3 x 0 first

7 - 4 + 0 + 1 = 4

maingate
03-11-2013, 08:34
Without brackets it ain't 4.

Not the way I was taught and I have Maths qualifications.

Maybe that is how kids are taught today. :)

rugbyken
03-11-2013, 08:41
Sorry no brackets on this equation on my I pad so ,
First look gives a total of 7,
Then of course there is 6 times nothing is nothing so we have 1 for an answer

Admin
03-11-2013, 08:42
You do Division and multiplication first, it is like having brackets round them. I was taught this at school.

outtolunch
03-11-2013, 08:55
You do Division and multiplication first, it is like having brackets round them. I was taught this at school.

I wasn't and I think this bit from Wiki sums it up nicely

Different calculators follow different orders of operations. Most non-scientific calculators without a stack work left to right without any priority given to different operators, for example giving
1 + 2 \times 3 = 9, \;
while more sophisticated calculators will use a more standard priority, for example giving
1 + 2 \times 3 = 7. \;
The Microsoft Calculator program uses the former in its standard view and the latter in its scientific and programmer view.

When the user is unsure how a calculator will interpret an expression, it is a good idea to use parentheses so there is no ambiguity

Admin
03-11-2013, 09:28
Order of operations - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Order_of_operations)

Admin
03-11-2013, 09:41
I would like to say that this was not an exercise in trying to make people look or feel stupid. I made the poll private and asked people not to comment.
I was taught BODMAS at a very young age and my seven year old Daughter got this question correct as BODMAS is taught in key stage 1 maths.

The point is that most people were not taught it!

Personally I think parenthesis (brackets) should be used and I cannot see a good reason why not.

8 - 2 * 6 = 36 wrong
8 - (2 * 6) = -4 correct

mark61
03-11-2013, 09:43
Everyone knows it was a trick question, the correct answer wasn't an option.

42. :p :lol-049:

Smaug
03-11-2013, 10:36
Without brackets it ain't 4.

Not the way I was taught and I have Maths qualifications.

Maybe that is how kids are taught today. :)

Haha, I was taught BODMAS in the 1950's and it was a well established practice then. In fact stuff like this was in the 11plus.

I have done maths beyond Fourier analysis, multidimensional differentials & statistics in my first & masters' degrees. I told yas all; yer wos wrong! :wacko::wacko::wacko:

Have you ever admitted being wrong in anything? - if only in thinking I was a "nice guy"? :lol-049:

Caz
03-11-2013, 10:48
I agree with Maingate, there's no brackets so the answer is 1.

Never heard of Bodmas and I passed my 11 plus in 1964 and O level maths in 1969.

(No use asking my kids what they were taught as they never paid attention and didn't pass anything. :rolleyes2:)

maingate
03-11-2013, 11:07
I am not trying to stir things Phil. It is all about the layout.

When I get a bit of time I will google and wiki this bad moss idea for further scrutiny. :p

As for that Smaug fella ..... yes, I was wrong once. I thought I had made a mistake but when I rechecked, I hadn't. :banana:

Nice guy my a**e. :raofl:

outtolunch
03-11-2013, 11:08
I agree with Maingate, there's no brackets so the answer is 1.

Never heard of Bodmas and I passed my 11 plus in 1964 and O level maths in 1969.

(No use asking my kids what they were taught as they never paid attention and didn't pass anything. :rolleyes2:)


I also passed the same in the same years and I cannot remember being taught Bodmas and believe it was glossed over to teach us the use of correct parentheses to avoid ambiguity as until scientific calculators became affordable most complex calculations would have to be worked the hard way with pen and paper.

Tezza33
03-11-2013, 11:11
My better half says nothing I do adds up so not worth me trying

Smaug
03-11-2013, 14:16
You do Division and multiplication first, it is like having brackets round them. I was taught this at school.

But there are none so blind as those who will not see. They are all doing the "sum" as if they were reading - from left to right. Funny how the "rules for reading" override the "rules for maths". I wonder how they would cope with transposing, multiplying or dividing matrices?

So much stuff we had to do by hand (& slide rule) before calculators & computers became readily available. I can remember doing scale drawings of room layouts with cardboard templates as a standard part of my work in the 70's & all the design calcs were by slide rule.

hextal
03-11-2013, 15:32
Everyone knows it was a trick question, the correct answer wasn't an option.

42. :p :lol-049:

But what is the question?:D

Admin
03-11-2013, 15:37
But what is the question?:D

Maybe we should build a supercomputer to find out?

Firefox
03-11-2013, 15:38
The answer is 4

You don't need brackets to say what to do in this case!

For example, if the expression 7-4+3a+1, you wouldn't evaluate it from left to right as (7-4+3)xa + 1, you'd find the value of a and work out what 3a was then proceed from there.

It's the basis of all maths and programming and engineering expressions.

maingate
03-11-2013, 16:37
There is one big flaw in this whole thread.

It was an Arithmetic question, not a Maths one. :p

Tezza33
03-11-2013, 17:38
They are all doing the "sum" as if they were reading - from left to right. Funny how the "rules for reading" override the "rules for maths".
That does explain why there are no Chinese entrants:confused:

Firefox
03-11-2013, 18:02
That does explain why there are no Chinese entrants:confused:

There were some, but they got -2 which wasn't on the answer sheet!

I can understand how people came up with 1 but how anyone comes up with 7, I don't get - it's a more popular answer than 4. No wonder we are getting overtaken by other countries.

Wooie1958
03-11-2013, 18:12
Come on then, own up, who put 9 ?

Smaug
03-11-2013, 18:13
There is one big flaw in this whole thread.

It was an Arithmetic question, not a Maths one. :p

Wriggle, wriggle, squirm. :dance:

Firefox
03-11-2013, 18:19
Come on then, own up, who put 9 ?

Three people got 0 too. Maybe it was the x0 in the middle that was the clincher for them!

Siimplyloco
03-11-2013, 18:58
No wonder the girl at our Co-Op can't add up!
John

Flipperdipper
03-11-2013, 22:05
It's simple

7-4=3
3+3=6
6x0 is still 6
6+1=7

:D

Smaug
04-11-2013, 09:43
It's simple

7-4=3
3+3=6
6x0 is still 6
6+1=7

:D

Do 2 wrongs make it right then?? :lol-049:

maingate
04-11-2013, 10:36
Do 2 wrongs make it right then?? :lol-049:

Yes. Two negatives make a positive. :lol-049:

NeilyG
04-11-2013, 12:29
It's simple
7-4=3
3+3=6
6x0 is still 6
6+1=7
:D

It's debatable whether 6x0=6 because 6x1=6

From what I can gather mathematics has a hard time with 0. Did you know that according mathematics objects should NEVER IMPACT? Think about it, if you drop a ball then mathematically it has to get halfway first, then halfway again etc., but never reaching ZERO because zero isn't half of anything!!!
Just not foolproof is it? http://www.bestemoticon.com/smiley/applaudissements/applause03.gif

Smaug
04-11-2013, 13:14
I can't believe people are taking this seriously! Any number of nothings must always be nothing, just try adding them up. :rolleyes2:

rugbyken
04-11-2013, 13:15
Did a 2 year BTech course about fifteen years ago rest of the course a doddle but when it came to the maths we were told the first year maths were A Level standard and the final year degree standard, so they brought in a real mad professor type , couldn't get himself down to a level that we plumbers etc could understand cracked wide open in the middle of an evening session said we were sabotaging his karma and he needed to go and lie down underground!!

maingate
04-11-2013, 13:36
Did a 2 year BTech course about fifteen years ago rest of the course a doddle but when it came to the maths we were told the first year maths were A Level standard and the final year degree standard, so they brought in a real mad professor type , couldn't get himself down to a level that we plumbers etc could understand cracked wide open in the middle of an evening session said we were sabotaging his karma and he needed to go and lie down underground!!

I applied to be a Plumber.

Because I had a Blue Peter badge, they said I was overqualified. :raofl:

Neckender
04-11-2013, 20:21
I applied to be a Plumber.

Because I had a Blue Peter badge, they said I was overqualified. :raofl:

You need a stetson to be a plumber.

John.

Asto
04-11-2013, 20:30
I was dubious from the start BECAUSE of the lack of brackets.

It is well documented that standards have fallen with new teaching methods, ambiguity was not present with the old ways I am thinking. :rulez:


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