To be slightly horrified at how poor my basic skills are?

[primrosesandmaths]

In my professional, graduate profession, I have just been told I have to work out something as a percentage.

I have no idea how to do it.

I shall google - it isn’t an advice thread as such, but my maths is just dire and I can’t help wondering if this is common or whether I am an imposter in my role.

So why do they still do times tables up to 12? Originally they used to do it because it was useful for shillings and pennies. And for feet and inches. But there's no point now. If there was any sense you'd do 2,3,5,7,11 and anything else'd be optional.
You’re right about the shillings connection. Until recently, children only had to learn up to 10 x in line with our modern metric system.
It was Michael Gove as Education Secretary who brought a 1950s style education back in.
Madness.

So why do they still do times tables up to 12

Because 6,12,24 etc is still a commonly used quantity, especially in logistics, because of it's symmetry. You still get cases of cans/tins in packs of 6/12/24 because they're easier to handle/transport as a 23 or 43 packing combination. A pack of 10 is 52 which is a cumbersome shape, and a 5 pack isn't even a regular flat sided shape at all. You need a pack side that is as close as possible to a square for ease/efficiency of packing and transportation. Whilst a 23 or 4*3 isn't a square, it's certainly better for packing than a 5 or 10 pack which would mean wasted space on pallets and in trucks etc. Even after decades of decimalisation, multi-packs in supermarkets are mostly based on the 6/12/24 model and in commerce/industry, pack sizes are usually in 12's.

Chardonnay I know someone who qualified as a PE teacher many, many years ago. Came out of teaching for many years, went back to teaching and now is a maths teacher.

This method works for any %

Yes, but only for working out the simplest of percentage calculations like a simple percentage of a single figure.

You can't use your method for working out:-

If sales increased from £1250 to £1375, what is the percentage increase?

If a business bought an item for £1000 including 20% VAT, how much VAT was charged?

If sales are now £1375 and increased by 7% over the past year, what were sales level last year?

These are the kind of percentages I imagine the OP needs to calculate, not simple ones like 10% of £100.

Creambun try BBC bitesize

I used to work in retail, the number of people who asked me how much 10% off £10 would be was shocking.

I'm an accountant. The amount of highly educated clients (including IT consultants) who pay £10 for petrol and claim back VAT of £2 (being 20%) is also shocking. That people working in IT and writing programs/databases etc have such a fatally flawed understanding of percentages has to be a worry. especially when some of them are actually working on financial/numerical systems.

So why do they still do times tables up to 12

Because 6,12,24 etc is still a commonly used quantity, especially in logistics, because of it's symmetry. You still get cases of cans/tins in packs of 6/12/24 because they're easier to handle/transport as a 23 or 43 packing combination.

So everyone has to learn their 12 times table because some people will go on to work in logistics and need to know how many tins there are in 6 packs? On that basis, people should also be learning their 24 times table.

If sales are now £1375 and increased by 7% over the past year, what were sales level last year? An everyday example of the use of algebra.

My kid who likes maths had FUN doing 13, 14 and 15 times tables. ( At home because they only do up to 10 in school, I'd added in 11and 12 from the start 'cos I'm Gradgrind.)

The problem is that I can only admit this on an anonymous forum or risk being labelled a dick.

So everyone has to learn their 12 times table because some people will go on to work in logistics and need to know how many tins there are in 6 packs? On that basis, people should also be learning their 24 times table.

Far more people work in logistics than work in jobs requiring them to solve simultaneous equations, calculate the area of a sphere, or need to know circle theorum. So why are those taught to everyone?

In any case, it's not as simple as counting tins in a six pack. It's how to calculate how many tins fit on a pallet or on a shelf, the best arrangement to fit the most on level, etc. Shop shelving isn't just randomly sized - it's all calculated exactly so that an exact number of tins/packets fits on a shelf. The supermarkets make an art-form out of it- the shelf stackers aren't just making it up as they go along, they're working from detailed plans/maps of exactly what goes where. That's entirely based upon mathematically symmetry right from the factory production line (in fact from the raw material suppliers) right through the supply chain to the customer's kitchen shelf. Logistics is a hell of a lot more than counting 6 tins in a packet! It's all about efficiency - pallets need to be loaded to full capacity, lorries need to be fully loaded for efficiency, etc. The efficiency of entire supply chains would be ruined if people started packing things decimally in 5's and 10's instead of symetrically in 6/12/24 using imperial.

If sales are now £1375 and increased by 7% over the past year, what were sales level last year? An everyday example of the use of algebra.

You don't need algebra. If you understand percentages, you just divide the end figure by 1.07. Far simpler than algebra.

I can't do maths. I can't even work out a percentage on a calculator. I a feeling of awful dread if I have to do anything with figures for my job.

People (especially teachers) make maths hard. Take prime numbers. You don't need to know that many - the first 20 or so is all that you'd ever need, and probably only the first 5 or 10 would get you through most school exams and real life scenarios for the average person.

So, rather than just tell the kids to learn 10 numbers off by heart, what do teachers do? They teach the formula for working out every prime number from 1 to near infinity. Realistically, how many kids are going to memorise a complicated formula and process, especially at primary school level when prime numbers are taught? Why not just give the damn list of the first 5 prime numbers for them to learn off by heart. Then once they've learned 5 numbers, give them another list of the next 5 to learn. There's not a single kid (other than those with a disability) who can't learn 10 numbers by heart.

Once they learn them, they're able to simplify and solve fractions, algebra etc. If they forget them over time, it's easy enough to write them in the front of their exercise book each year as a reminder and help them remember for when it really matters in their exams. But, no, schools teach them how to work out prime numbers, so in an exam, they have to spend valuable time working through the formula (if they remember it) to create their own list of prime numbers! Crazy stuff!

Realistically, how many people need to know whether 1,179 is a prime number? 1%, 0.1%, 0.01%? So which teach the formula to the other 99%? For those who are in professions needing to know whether 1,179 is a prime number, they'd have "crutches" at their fingertips, such as calculators, computer programs, spreadsheets, apps, or whatever so even they don't need to know and don't need to calculate it by manual formula methods!

I too have a complete lack of skills in arithmetic and maths and anything to do with numbers. I cannot even work out simple things like how much change from £5 for something that costs £2.87. I just get totally flustered and take a wild guess.

I have always been this way. I probably have discalculia, although it's never been formally diagnosed. I often get numbers mixed up, phone numbers especially. Someone tells me their number is 123654 and I write it 132654.

At infants school we used to have mental arithmetic sessions where the teacher would bark out something like "3 times 7" and then choose a child to answer the question. I was so nervous about these sessions that I sometimes used to wet myself, for which in those days I would receive a smack on the legs and be publicly humiliated by the teacher. I still remember that feeling of dread when "mental arithmetic" was announced. I was 6.

I cannot even work out simple things like how much change from £5 for something that costs £2.87. I just get totally flustered and take a wild guess.

I started serving in my parent's corner shop when I was 11 years old. We had no tills, so we had to add everything up in our heads and calculate change ourselves. The simplest way is simply to "count up" from £2.87 to £5.00. Start with £2.87 in your head, then take 3p out of the till to make it 2.90, then 10p to make it £3 then two pounds to make it £5, and hand the £2.13 in your hand to the customer. Simple when you break it down to it's simplest level. It's just another thing that teachers make hard which makes people think it's too complicated.

They teach the formula for working out every prime number from 1 to near infinity.
There is no formula for working out primes.
Why not just give the damn list of the first 5 prime numbers for them to learn off by heart.
Because it is much better (and in the long run easier) to understand why a number is a prime rather than to rote learn which numbers are primes.

Isn't that basically what we have? GCSE maths, particularly if you're not in a top stream will be every day mathematics

Trigonometry, solving simultaneous equations, solving quadratic equations, circle theorums, angles of spheres, ISN'T everyday mathematics. Sure, there are some more basic questions such as averages, compound and simple interest, areas, basic algebra, basic percentages, etc., but an awful lot is completely irrelevant to probably 90+ of the population. That's probably why you can still get a "good pass" grade when you gain only 30% (or less) marks on the paper. There's far too much advanced stuff on it which the majority of kids will never grasp and upon which a massive amount of teaching time is wasted, and is no doubt why so many people believe they are crap at maths. (They're being set up to fail by the system and teachers).

Personally, I think the 11+ maths paper is far more useful to the average Joe Public

There is no formula for working out primes.

OK, if you're being pedantic, not strictly a formula in exact terms, but a system/procedure for working out which numbers are prime. But I stand by my point - for school/average Joe Public purposes, simply remembering the first few prime numbers is far simpler and would take far less teaching time, and help reduce the "i can't do maths me" culture.

I totally agree with the poster who said that previous generations learned fewer things more thoroughly in maths. I’ve been an infant teacher all my life and was educated in the 60’s and early 70’s, I am now 61. Our maths and literacy skills were drummed into us and I can work out percentages in my head.
I am appalled at how children are expected these days to be taught a skill once and then have no time to consolidate as it is straight onto the next thing.
I have also had to help graduate teachers with basic maths skills in order for them to teach 7+. I wasn’t considered to be brilliant at maths at school, but it was definitely taught in a way that has proved to be useful in everyday life.

I am appalled at how children are expected these days to be taught a skill once and then have no time to consolidate as it is straight onto the next thing.

Or weren't even taught them in the first place. My son is year 11, top set Maths, just got a grade 9 in his mock GCSE. They spent yesterday's lesson "learning" long division. Apparently, not a single pupil in his class got the long multiplication question correct in the GCSE mock, hence the teacher "teaching" them "again". All deny ever having being taught it previously. Teacher argued that it should have been done in primary school. But how on Earth did they get through 5 years at secondary without any teacher "noticing" that the pupils hadn't been taught something so basic and why hadn't it been included in previous tests, end of year exams. It's a bit bad when the first time such a problem is identified is the mock GCSE just 2 months before the real thing.

But I stand by my point - for school/average Joe Public purposes, simply remembering the first few prime numbers is far simpler and would take far less teaching time, and help reduce the "i can't do maths me" culture. Surely it's better to teach what primes are which would mean that you would need to remember one thing, not ten things?

And also, not teaching maths is is exactly the thing that might lead people to think that they can't do maths...

There is no formula for working out primes.

^^ I thought this as well - otherwise why would people need vast computing power to find the next known prime.

Mine have been taught what primes are - numbers divisible by only themselves and 1 - that's not a formula it's a definition and it's needed to identify them.

They've then done bit of work identifying the first few ones and rather than a random list of numbers they've understood why they are prime. Also means if they go past the first ten or so they can still identify numbers as prime.

For at least one of mine lists of things aren’t great but when they understand and have to apply maths it eventually sticks.

The main issue I can see with maths teaching currently is not enough basic practise for children.

Plus some teaching at younger levels is focused on “fun activities” which are time consuming and if you have easily distractible children with poor short term memories like my DS mean they can forget the principals before the activities have been set up and end up confused.

Wales has already split its maths GCSE maths qualifications into mathematics and mathematics numeracy. Which seems to be what a lot of posters are suggesting needs to happen.

OK, if you're being pedantic, not strictly a formula in exact terms, but a system/procedure for working out which numbers are prime

Since the time it takes to factor large composites into their component prime numbers is one of the fundamental issues is computer security, and a problem that MN readers exploit every time the little padlock pops up on a web page, it would be nice if people had some understanding of why it's conjectured to be hard. I think it's interesting that MN is full of people bemoaning their lack of knowledge about computers and saying that they want their children to know more, while at the same time advocating stripping the maths curriculum of absolutely fundamental knowledge.

Mine have been taught what primes are - numbers divisible by only themselves and 1

Numbers greater than one, divisible only by themselves and 1. 1 is not prime. Quite a lot of fundamental stuff breaks without the distinction that 1 is not prime.

@SpringMayHaveSprung

There are tons of other websites out there with better material and Khan Academy has a huge political bias too, so I'd avoid it more than the plague.

I think I remember hearing about how Google was making us less 'scared' to remember things that otherwise we would have remembered - almost like our brains being efficient.