Nfer maths 11A Q47.

yoyo123 · Post by **yoyo123** » Wed Aug 27, 2008 4:14 pm

I have to admit I have never mastered short division

i was taught long division at he beginning of what is now year 3 and was fine with it. Then moved schools from Wales to England and they did short division. They laughed at me when I said i couldn't do it and I was too terrified to ask again.........

didn't do me too much harm in the scheme of things as i went on to do complicated physical chemistry calculations, but i still have a 7 year old's dread of short division!

Snowdrops · Post by **Snowdrops** » Wed Aug 27, 2008 4:27 pm

I have been teaching dd the 'old way' as I find it far, far quicker and discussed working out methods with my dd's techer when I started self tutoring last year.

(We are out of area for 11+)

I explained to the teacher (but am sure she already knew) that speed was of the essence and called for a different method from what was taught in class.

I also explained, to the teacher, I had told my dd that she learnt one way for 11+ but had to do school's way in school and that I wasn't trying to undermine what was taught in school.

Teacher said dd was more than capable of learning both ways and that once they all moved up schools they would learn different methods anyway.

It was surprising how quickly dd took to the old ways and uses it very easily. It's good to see her quickly working out some quite long mutiplications and divisions which otherwise would have taken a longer time.

I say if you can teach it do it, but do make sure they understand they are two different methods and must be used appropriately!

Tolstoy · Post by **Tolstoy** » Wed Aug 27, 2008 4:57 pm

I asked my son's teacher about the teaching of long div/mult and she also said that they will go on to a different method but the feeling was that starting with this new method gave them a better understanding of the maths. Both husband and I have maths A'level and yet found it a tad complicated to say the least. Also the teacher herself didn't seem overly confident explaining it to us. I am a trained teacher and she had my sympathy.

When I taught my son the old way I started by re-inforcing T/U to make sure he understood what we were doing. Suppose it is easier one to one?

Guest55 · Post by **Guest55** » Wed Aug 27, 2008 5:04 pm

There is a real advantage with the grid method of multiplcation when you come to algebra -

yoyo123 · Post by **yoyo123** » Wed Aug 27, 2008 5:24 pm

i like teh grid method too, it's not designed to be done as a complete alternative but it really does getteh children to think abiut what multiplying really means.

it;s easier to master than short division anyway!!

ergo · Post by **ergo** » Wed Aug 27, 2008 8:09 pm

Am I being completely dense here? Could the guest explain how they immediately knew that 8% of 12 was 1.5 so that I could show my child how to work it out quickly? Thank you

Guest55 · Post by **Guest55** » Wed Aug 27, 2008 8:15 pm

In the question we are told 8% are lime.

We also know 12 trees are lime.

So 8% of total trees is 12. If we divide by 8 to get 1% then

1% is 1.5 trees -

Lulu · Post by **Lulu** » Wed Aug 27, 2008 9:52 pm

Ok, but why do the sum 12 divided by 8? Why not leave 1% as a fraction i.e 12/8 and then multiply by the % you need to find.
When the sum becomes 12/8 x 42/1,(written properly one number on top of the other, which I couldn't manage on my keyboard) a child should see a series of even numbers and then start cancelling down using the 2 times table (to keep it simple) and eventually get to 3/1 x 21/1. Or is cancelling down a bit old fashioned too?

Guest55 · Post by **Guest55** » Wed Aug 27, 2008 9:57 pm

It's better to call it simplifying .. I would probably keep it as 2% to avoid fractions or decimals - multipying fractions is harder than multiplying decimals like this.

Lulu · Post by **Lulu** » Wed Aug 27, 2008 10:22 pm

I agree, decimals are easier to use than fractions!