Okay, I've just been explaining how to add, subtract, multiply and divide fractions to son no.2.

No problem. But then his teacher gave questions with three or more fractions.

e.g. 4/7 + 10/5 x 2/6 ...etc

My first thought was that in the absence of brackets, you do it left to right.

But the teacher has said that in the absence of brackets, calculations are done in the order mdas and gave them "My dear aunt Sally" to help them remember!

Is this right? It's been soooo long since I did sums like this.


Steve

Yep, "my dear aunt sally" is correct.

PS> That's how it works in MS Excel and scientific calculators as well, so if you want to do +/- first, you have to add brackets

We used to use BODMAS Brackets Off, Divide, Multiply, Add, Subtract These days I think they use (obviously at a higher level) BIDMAS = Brackets, Indices, etc,

In THIS case multiply first. I hope I'm right!

Ah, thanks!

Mind you, if I ever find this Aunt Sally....!!!

Steve

Gee, thats the first time Iv'e seen BODMAS since the 1960's !

Yup, guess when I went to school!

Aye, BODMAS here too.

Ours was BIDMAS

Brackets, Indices, Division, Multiplication, Addition, Subtraction

I'm still at school and my teachers always tell us to use bodmas. Never heard of mdas.
But it seems that they are both the same except the multiplication and division thing which have been inverted but that does not make much difference to the answer obtained