BODMAS Rule application

[burgess]

Today I want to share what Is BODMAS Rule & How to use it?

 

BODMAS rule decides the order of operations for add, subtract, multiply, divide, etc as below shown

B-Brackets (do all operations contained in the brackets first)

O-Orders (powers and square roots etc)

D-Division

M-Multiplication

A-Addition

S- Subtraction

 

Lets see an example and check how BODMASS Rule works

30-(2*6+15/3) +8*3/6

 

Step1: Brackets

2*6+15/3 = 12+5 = 17

 

Step2: Division

30-17+8*1/2

 

Step3: Multiplication

30-17+4

 

Step 4: Addition and Subtraction

30-17+4=17

 

 

20+30-5/4*2+ (1+6)

(5-6/4)+9*7

1-6*(2+9)/8

 

 

BODMAS Rule is very helpful in solving various algebra math problems.

[pzkpfw]

I would argue that multiplication and division are of equal precedence (they're basically the same thing) so are done left to right, in the absence of modifiers like brackets.

 

The same goes for addition/subtraction. After all, if you really wanted to do addition before subtraction, the step 30-17+4 would come to 30-21 giving 9, not your (which I think is correct) 17.

 

i.e. BO{DM}{AS}

 

So ... where you show the end bit as 8*3/6 then 8*1/2 giving 4; I think that ought to be 8*3/6 then 24/6 giving (luckily the same in this context) 4.

 

I'd show the thing, in very long form, as:

 

30 - (2 * 6 + 15 / 3) + 8 * 3 / 6

 

= 30 - (12 + 5) + 8 * 3 / 6

 

= 30 - 17 + 8 * 3 / 6

 

= 30 - 17 + 24 / 6

 

= 30 - 17 + 4

 

= 13 + 4

 

= 17

Edited August 8, 2014 by pzkpfw

[harshgoel1975]

I think writing 30-(2*6+15/3) +8*3/6 should be written as 30 -((2*6)+(15/3))+(8*(3/6)) now life is simple and more mathematical... just open the inner brackets first then bracket then follow any method you want.... problem here is that we don't put sufficient brackets and make the sum complicated.. then we try to put some rule around that to solve it.. unnecessarily..

30 -((2*6)+(15/3))+(8*(3/6))

30-(12+5)+(8*0.5)

30-17+4

17

no wonder why some kid hate maths...

[ajb]

BODMAS does not really help you solve anything, it is guide to notational convention and nothing deeper. That said, it is useful when learning basic algabra.

[harshgoel1975]

BODMAS does not really help you solve anything, it is guide to notational convention and nothing deeper. That said, it is useful when learning basic algabra.

But not following it would give incorrect results...so why not use right convention...

[ajb]

But not following it would give incorrect results...so why not use right convention...

But how can a convention be right? What you mean is that we have all agreed on a convention and that BODMAS is a nice way of remembering that convention. But there is no reason why I could not apply some other notation or keep similar notation but change conventions. My mathematics would be just as right as yours, notaion is important but it is not the same as the mathematics itself, we would both be describing basic algebra. However, it may be difficult to compare results without some care.

 

Now, that is not that I am suggesting we change conventions or notaion here for basic algebrs, the point is we have picked some notations and conventions alongside the notation.

[harshgoel1975]

But how can a convention be right?

 

if a convention gives meaning without ambiguity it is right

 

BODMAS is a nice way of remembering that convention. But there is no reason why I could not apply some other notation or keep similar notation but change conventions.

correct is better than nice

 

in nutshell...30-(2*6+15/3) +8*3/6 can be better written as 30 -((2*6)+(15/3))+(8*(3/6)) as it gives unambiguous result ... just a two cent idea....

[ajb]

if a convention gives meaning without ambiguity it is right

All convenions should do that.

 

 

in nutshell...30-(2*6+15/3) +8*3/6 can be better written as 30 -((2*6)+(15/3))+(8*(3/6)) as it gives unambiguous result ... just a two cent idea....

I agree, using parentheses can remove ambiguity, or at least when used with BODMAS!

 

I am not arguing against the standard notation, parentheses and BODMAS for basic algebra, I am just pointing out that it is all tied into conventions relating to notation.

[harshgoel1975]

I agree, using parentheses can remove ambiguity, or at least when used with BODMAS!

 

I am not arguing against the standard notation, parentheses and BODMAS for basic algebra, I am just pointing out that it is all tied into conventions relating to notation.

Thanks...so I suggest mathematical societies to review the notation if not already reviewed..in this context...

[Royston]

Thanks...so I suggest mathematical societies to review the notation if not already reviewed..in this context...

 

I can think of a number of conventions (within maths and especially physics) that could do with an overhaul. The problem with doing this, is that could become more of a hindrance than a help. Conventions ensure that everyone is on the same page, regardless of whether they're unintuitive or more cumbersome to use. I can understand why this seems a little silly.

 

In this instance, if adding extra brackets reduces ambiguity (or helps) in your calculations, then use it. At this level of algebra it really doesn't matter.

[Daedalus]

Sure BODMAS could help you remember the order of operations, but why not let FEMA manage the emergency:

 

Functions / Groupings
Exponentials / Roots / Logarithms
Multiplications / Divisions
Additions / Subtractions

 

Edited August 11, 2014 by Daedalus