To Floopy. assuming you're genuine about the idea five times nothing is still five.

I did GCE O level, AO Level and A level Maths.

If there's one thing from Secondary school I remember it's the delights of the numberline.

The Addition Property of Zero: the sum of any number and 0 is the number you started with: try 40+0 on your calculator. It follows that 40-0= 0 too.

In the Multiplication Property of Zero, the product of any number with zero is zero. Try 40x0 on your calculator.

The Zero times table is a synch and

For completion if you divide any number by 0 you really oughtn't. http://gcse-math.co.uk/algebra/division-by-zero

0 + 0 + 0 + 0 = 4?

No, it doesn't.

You are, as stated earlier, attempting to argue that 1=0, and by extension that you know better than anyone who has ever taught or studied maths or has participated in any field that has anything do with maths whatsoever, and that all of those people have fundamentally misunderstood one of the most basic rules of the universe.

Bit daft, eh?

Ach, I hate to think how that will be explained using 'logic'.

I modified my mail whilst you were typing. Integers are fun, ain't they?!

1 + (-1) = 0

It won't convince Floppy, I don't suppose, but this is the sort of thing GCSE students'll be revising in the weeks to come.

http://gcse-math.co.uk/number/number-operations

Floopy123, I really hope you one day study math as your results above show that you are someone who would really benefit from this type of study. Then you will see it does all really make sense. And you can definitely have negative numbers in a bank account too even if I wish it would remain at 0!

The Open University offers a course which acts as an introduction to very basic maths. I really hope you do it one day.

Here are some pointers:

10 * 0 is the same as 0 * 10 so = 0
10 + 0 is the same as 0 + 10 so = 10
10 - 0 is not the same as 0 - 10 = as 10 - 0 = 10 and 0 - 10 = -10

The order of negative and positive numbers from -10 to 10 is:

-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10

When calculating a sum without brackets, the ordering of calculation is:
1) multiplication & division first
2) adding and subtraction second
You don't do math in the same was as reading and just do left to right

HTH

Multiplication means repeated addition.
If you have 4 bags of crisps on the table, multiplying 2x4 is like having 2 groups of 4 bags on the table.
Multiplying 1x4 is like having 1 group of 4 bags on the table.
Multiplying 0x4 is like having no groups of 4 bags on the table, hence no bags at all.

But if you had four lots of nothing, i.e. 4 x empty boxes, you'd have nothing, wouldn't you? So 4 * 0 = 0

Ignoring the troll, I think the big issue with Maths is that it has become the social norm to be bad at it. Kids are taught by their parents and peers that it is "difficult" and therefore they shouldn't try unless they're "really smart".

networkbabe - I believe the teams had lists of how much the product would cost to produce at different quantities and they also had a selling price. This means they strugged to figure out that profit per item = sale price - buy price and that the percentage profit = profit per item/buy price. That's kind of scary for people who run their own businesses.

Maths is the most logical discipline you can study. I really can't understand why so many people shirk away and proclaim it "difficult" yet they'll gladly learn the rules of a new language or science.

5 doubled once is 10 (not 5 as you say)
5 doubled twice is 20 (not 10 as you say)

5 "doubled once" is not the same as 5 x 1
5 "doubled twice" is not the same as 5 x 2

You seem to have trouble with English as well as Maths.

Essentially by saying 40 x 0 = 40 you are trying to prove 1 = 0. This is manifestly wrong, or as mathematicians call it, bollocks.

If you work out equations left to right then your arithmetic earlier in the thread is valid. However the rest of the world accepts the BODMAS convention. With good reason as simple arithmetic won't get you far in mathematics. I wish you luck trying to upset this long established and very useful convention with the much less useful "left to right" idea.

It's long been thus. I was at school in the 1960s and even then being good at maths was seen as uncool. Some people do have a mental block about maths, so for them it is genuinely hard.

Anyway, what these people aren't good at is arithmetic, maths is far more than calculation. Under pressure it's not surprising they make mistakes though. No doubt in normal circumstances they'd have no trouble working out simple arithmetic. You also see this in Dragon's Den when competent business people freeze completely with nerves under pressure.

The girls mistake this week was pitching Amazon with margins when they didn't seem to understand the meaning of the term. If they'd pitched them wholesale prices there would have been no embarrassment.

Oh the irony.

A very lively discussion, I must say.

I might add the reason there are rules in maths is to avoid discrepancies such as the ones being discussed, but poorly presented sums can also add to the confusion IMO. If you don't follow the rules Maths can be frustrating, so the solution is simple, know the rules.

Why is maths so uncool, I've never understood? Without mathematicians we would never have computers and the like, that's pretty cool IMO. The mathematician Alan Turing and his fellow code breakers at the top secret Betchely Park were one of the key reasons we won World War 2, what's uncool about that?

Yes the candidates are under some pressure, but the fact they all fall to pieces and have no confidence in their own grasp of profit/loss and margins is embarrassing. It's almost as if they hope the people they are pitching too have as limited a grasp as they have themselves.
Yes I agree that most businesses employ accountants to ensure that figures are correct but hey, multiplying £7.34 by 1 million is not rocket science even if it is an unrealistic goal sales wise.

That's the problem; I think few people after leaving school remember BODMAS, as few people will ever need to remember it after school. That's not because they don't need to be numerate, but because they will know themselves whether they want to add two figures before multiplying them by something else, or whether they want to multiply two numbers and then add something on to the result.

I work in a pensions office and do calculations day in, day out, yet I've never thought of BODMAS until this thread, although we did learn it at school. If presented with the initial sum 3 + 7 x 4, I'd get 40, just as you've done, and for the same reason. Fortunately in real life we are rarely presented with sums that are deliberately presented in a way designed to trap us.

To be fair to the candidates, I also work with numbers everyday but my maths (not the basic stuff, but the more difficult stuff) is also a bit shaky as I mainly work with Excel sheets.

Having a financial job does not automatically mean that you are very good at maths, just that you should know about financial terms like mark-up and profit (which was were the girls got confused).

I think that as a society there are ingrained problems where the advance of science, maths, and other areas are leaving "the common man/woman" behind. And our response as a society has not been to accept that people must specialise and that we need to defer to those who know what they are doing even if we don't understand it. Sort of like the following example from Wikipedia:


This doesn't just happen with maths, but also medicine, climate science, and other areas. People reject modern science and learning and decide that they personally know better than these boffins/geeks.

Returning to the topic of TA, I'd say that the same is happening in business, and the apprentice candidates are evidence of that. They are plumped up know-nothings in many cases (Ruth Badger would be an example of someone who knows what she was doing) who substitute unrealistic self-confidence and meaningless slogans for actual business knowledge and skills.

I'm not sure if floppy is trolling or not, but if s/he isn't trolling, then this would be another example. Instead of learning and accepting the proper way of doing things, there's a blustering insistence that floppy knows best and mathematicians don't know what they are talking about. Apply that sort of blustering ignorance to business and you get the apprentice candidates. Apply that to medicine and you get crystal healing. The list goes on.

galculator >calulator.

This is the perfect answer to the 10 x 0, 0 x 10 query.

10 x 0 means that I have ten lots of nothing.

0 x 10 means that I have no lots of ten.

Either way I have nothing.

Surely it's also because BODMAS is hard to remember.

Are people actually taught BODMAS?

I think it's a terrible way to expect people to remember the precedence rules. They have to remember a meaningless "word" and then they have to work out what the letters stand for. No wonder many forget!

Even though I know the rules, I'm struggling to work out what BODMAS stands for. What the heck is the "O"?

Is there even a memorable sentence whose words start with the same letters (like "every good boy deserves fudge")? (According to Wikipedia, in the US PEMDAS and "Please excuse my dear Aunt Sally" are often used.) (P is parentheses and E is exponentiation.)

BODMAS is also misleading, and potentially confusing, because it puts Addition before Subtraction and Division before Multiplication when they actually have the same precedence.

And BODMAS does not help at all with the order of other operators (which are common in many parts of maths and in programming languages).


Yes, exactly. It is a language and, as such, its rules are somewhat arbitrary (within limits) but learnable.

And the rules make more sense if it's remembered that in mathematics, multiplication usually isn't written as "x" but instead just by putting things next to each others. For example, three times n is written "3n" rather than as "3 x n". And then

3n + 4n

"looks like" the multiplications are done before the addition.

The "O" stands for "Order" or "Of" or "Over" - its a bit misleading as it refers to powers as in Einsteins famous
E=MC2 where you square the speed of light (C) before you multiply by mass (M)

Yes addition/subraction are the same precidence but how could you have a mnomic without some sort of implied precidence? Since addition/subtraction and multiplication/division are commutative it doesn't actually matter that BODMAS tells you to do one before the other.

That's not quite right.

The Wikipedia entry for Order of operations gives a handy example.

10 - 3 + 2 = ?

The correct answer is 9 (which you get by doing the subtraction first), not 5 (which you'd get by doing the addition first).

That an operation is commutative does not tell you what happens when different operations occur. Both multiplication and addition are commutative, yet the whole point of this thread is that in maths, multiplication is done before addition.

The Wikipedia entry explains the above example by pointing out that it's equivalent to

10 + (-3) + 2

And you can indeed do those additions in any order.

The point of the implied preference in the BODMAS acronym (although to make things more confusing, I was taught BIDMAS which actually means exactly the same thing ) doesn't matter. Follow the acronym, get the right answer although you are absolutely correct that subtraction has equal precedence with addition.

Alternative mnemonics are BIDMAS where the I stands for "index", and BEDMAS where the E stands for "exponent".

Er, im poor at maths but even i knew it was 31. The multiplication bit goes in brackets. I couldn't even begin to explain why, I just followed orders in maths class.

It was just one of two of them. Jane took it for granted they'd be capable; it was a surprise to everyone when they weren't.

I think this show could help encourage numeracy more, if it gave out more of the detailed figures. Ideally on You're Fired, but failing that, on the website.