Son's teacher needs to go back to school

onlyroz

If it helps you to interpret something like "> 30", try putting in a dummy symbol so that it reads "x > 30", which clearly reads "x is greater than 30". Then all you have to do is remove the x again, so you're back to "is greater than 30". Simples.

Wickedkitten

Poppy9 wrote: »

My DD is 16 and has come through the "new way" of teaching maths.

If I remember correctly for the first 2 or 3 years she only did mental maths and used approximation to work out answers so rounded numbers up, down to 10 to add and then took away the odds that she had rounded up - I explained that really badly but if faced with 3 x 9 she would round up 9 to 10, multiply by 3 to get 30 and take away the 3 ones she added to round up!

I remember he showing me how she did long division and I was lost, I was happy to keep my mouth shut on my method as I thought it would confuse her but she wanted to see how I did it and declared her way easiest!

She's now doing A level maths as she enjoys it and her maths skills are excellent, partly I believe because a lot of emphasis was put on maths in her primary.


Last summer when she was helping a friend with revision for her maths GCSE she asked me what something like 27 x 19 was and I spoke aloud going 10 x 27 is 270 so double it 540 and take away 27 = 513.

DD said yes I agree but I did 30 x 20 so 600 and then took 3 x 20 away so 540 and then took away 27.

Her friend was amazed we could both work it out in our head and our different methods. She attended a different primary school and said she had never really done mental maths.

I've always done it the way your daughter does as well :beer:

Tigsteroonie

Just want to add my voice to the crowd (seeing as I've read the entire thread) ..

To me (traditional 70s/80s Maths) the symbol '>' always means 'is greater than'. Whether on its own, prefixed by anything, or suffixed by anything.

Humphrey10

http://en.wikipedia.org/wiki/Greater-than_sign

It's the position of the symbol in relation to the numbers that matters, not the name of the symbol:

x>30 then x is greater than 30

30<x then x is greater than 30, it's not less than 30 just because there is a 'less than' sign there

It doesn't matter if you read it (the expession, not the symbol) right to left or left to right, the meaning is the same.

the smaller end of the symbol, the point, points towards the smaller number, the larger open end points towards the larger number.

Sambucus_Nigra

Tigsteroonie wrote: »

Just want to add my voice to the crowd (seeing as I've read the entire thread) ..

To me (traditional 70s/80s Maths) the symbol '>' always means 'is greater than'. Whether on its own, prefixed by anything, or suffixed by anything.

This symbol > means the thing on the left is greater than the thing on the right. It also means the thing on the right is less than the thing on the left

This symbol < means the thing on the left is less than the thing on the right. It also means the thing on the right is greater than the thing on the left.

As pointed out by Humph - it's the context and placing that's important to the result and to what you call it.

bestpud

welshgirl78 wrote: »

Clearly you are aiming not to understand me, or you have less understanding than you realise.

Literally, as you read it, the sign is traditonally less than, and therefore the statement can be read as "less than" 30

If you have geninue concerns about my ability we can discuss it further. I have no concerns. I was merely pointing out that as a teacher it is interesting to understand Why someone has that misconception rather than just saying they are wrong.

Surely it is a little concerning that you interpret a comment (however incorrect you may believe it to be) as an opportunity to demean all maths teachers. I hope we are not solely responsible.

Please enlighten us!

How on earth can that be read as 'less than 30'?

bestpud

OP - you should speak to the teacher and she then needs to tell your son he was right after all, and hopefully make sure she hasn't confused an entire class!

Hopefully you aren't the only parent who has noticed this!!!

However, if a lot of them got that one question wrong, you'd think she'd have noticed and checked for possible reasons...

*max*

Sambucus_Nigra wrote: »

This symbol > means the thing on the left is greater than the thing on the right. It also means the thing on the right is less than the thing on the left

This symbol < means the thing on the left is less than the thing on the right. It also means the thing on the right is greater than the thing on the left.

As pointed out by Humph - it's the context and placing that's important to the result and to what you call it.

We read from left to right, so to me the sign matters more than the placement of x in relation to it. But we are fundamentally saying the same thing anyway, let's not confuse people anymore than necessary. lol

Sambucus_Nigra

*max* wrote: »

We read from left to right, so to me the sign matters more than the placement of x in relation to it. But we are fundamentally saying the same thing anyway, let's not confuse people anymore than necessary. lol

Sorry, but no we aren't. The whole point of the signs is that it matters what is on each side.

So >30 means 'greater than 30' and 30> means 30 is greater than - both are right but with the same sign.

*max*

Sambucus_Nigra wrote: »

Sorry, but no we aren't. The whole point of the signs is that it matters what is on each side.

So >30 means 'greater than 30' and 30> means 30 is greater than - both are right but with the same sign.

Yes we are, I can assure you. I said "to me", it's just the way I read it.
Since we read from left to right, the sign ">" always means "greater than". I am not arguing, there is no point: we are saying the same thing! Anything else is just rhethorical.