Maths question

[Noughtboy]

I went about it s different way. To me the first question to answer was to do with inversions of the original equations to get whole numbers making it easier to understand. I am on the phone so will have to type in the answers to make it easier.

240/(24/5760). So to "fix" the top we divide both sides by 240. Thus:

1/240=1/(24/5760).

To get to whole numbers, we can invert both sides. Thus:

240=5760/24 which without knowing the answer, looks like this:
x40=57y0/z4

We can now multiply both sides by z4. This:

x40xz4=57y0. Now we see that y is 6 because 40(the ten)*4(the unit)=160. So the answer or RHS is 5760.

Then, we can say z4=5760/x40 or to make it easier z4=576/x4 and after that I would tell them to plug in starting with twos and ones and moving up as necessary as I do not remember all the tricks.

To me it is explaining the logic of doing inversions in complex questions to get a simpler equation then solving for "x"

 

[Angilion]

Thanks for the explanation, I was thinking along the same lines in that it is all just trial and error, this seems pretty hard for 10 year old kids. My lad can do division using bus stop method or chunking but this I think is a little bit tough for them at that age. I suppose you could class it as reasoning but even so, that is not easy. I am seeing his maths teacher later this week anyway on a parents evening so will ask what it is all about then.

I can think of two possibly relevant things:

The method makes it necessary to perform the task repeatedly, i.e. more practice.
The method might be useful for learning to approximate for error checking and the use of knowledge and logic to create shortcuts rather than merely following a general method line by line like a computer.