BIDMAS
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Surferfish
- Posts: 682
- Joined: Fri Mar 10, 2017 5:06 pm
Re: BIDMAS
Well the OP was obviously confused about something to have posted the question in the first place. If it wasn't that what do you assume it was?
Just to clarify what I mean about the possible confusion, first consider the following sum:
10 - 3 x 2 - 1 = ?
So following BIDMAS you'd think, ah, Multiplication comes before Subtraction so I do the multiplication bit first. That gives 10 - 6 - 1 = 3. The correct answer.
Now consider this very similar looking sum when written down:
10 - 3 + 2 - 1 = ?
Surely its not too hard to imagine that a child with limited understanding might think, ah BIDMAS again. Addition comes before Subtraction in BIDMAS right, so its just like the first one, and I'm supposed to do the addition bit first. So that gives 10 - 5 - 1 = 4. Which both you and I know is wrong, but surely a fairly understandable mistake for a 6 year old to make, no?
Just to clarify what I mean about the possible confusion, first consider the following sum:
10 - 3 x 2 - 1 = ?
So following BIDMAS you'd think, ah, Multiplication comes before Subtraction so I do the multiplication bit first. That gives 10 - 6 - 1 = 3. The correct answer.
Now consider this very similar looking sum when written down:
10 - 3 + 2 - 1 = ?
Surely its not too hard to imagine that a child with limited understanding might think, ah BIDMAS again. Addition comes before Subtraction in BIDMAS right, so its just like the first one, and I'm supposed to do the addition bit first. So that gives 10 - 5 - 1 = 4. Which both you and I know is wrong, but surely a fairly understandable mistake for a 6 year old to make, no?
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Surferfish
- Posts: 682
- Joined: Fri Mar 10, 2017 5:06 pm
Re: BIDMAS
Well you'd know more about that than me, but I have to admit that I'm pretty impressed that the average 6 year old these days understands the concept of numbers having a sign belonging to them. When I was that age ' - ' just meant 'take away'!Guest55 wrote:Switching the order is taught in schools - it's basic to understand the sign belong the the number following it.
This approach starts in KS1 ..
Re: BIDMAS
Thanks all. I was simply confused about whether to apply BIDMAS when there are no brackets. As someone else mentioned this does change the answer if you follow the BIDMAS rule, as opposed to simply going from left to right.
Re: BIDMAS
NO, in the example you posted you get EXACTLY the same answer.MCLC wrote:Thanks all. I was simply confused about whether to apply BIDMAS when there are no brackets. As someone else mentioned this does change the answer if you follow the BIDMAS rule, as opposed to simply going from left to right.
