Re: Multiplcation Not Repeated Addition- Explain
Posted by: Teacher on 6/28/09
Yes, but if you explain that multiplication sign means "of" I think it will
clear things up. You can show them a model of this by having kids fold a paper
one way, and shading the fraction, and then folding it for the next fraction
and shading the squares for the second fraction. They can visually see that
it's a smaller number. I'm sure that they will find something to fuss about
saying "of". But even in the other guy's example, he is essentially using of.
He said something about 2 * 6 is like saying 2 six packs OF soda. Or 2 groups
OF 6.
On 6/28/09, Juliana wrote:
> On 6/28/09, DD wrote:
>> Juliana, I see your explanation, but multiplying numbers greater than
>> 1 always gives a product (or a sum if using repeated addition) that is
>> greater than the two numbers you are multiplying. When multiplying
>> numbers less than 1, I think some students will be confused as to why
>> you get a product less than the two numbers you are multiplying. That
>> might be where the repeated addition doesn't foster true understanding
>> of multiplication.
>
> Students already are going to be confused by that. They simply need to
> learn that multiplying fractions means doing both multiplication *and*
> division -- that a fraction is one way of indicating a division problem.
>
> Anyhow, students surely do understand what half OF something means. If they
> can once really get it into their heads that one-half TIMES something is
> the same as one-half OF something, they're well on their way.
