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Solve 6-1x0+2/2


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#46 vetneufuse

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Posted 05 September 2012 - 18:06

It's 7. However, BODMAS and PEDMAS are both silly; Division is the inverse of multiplication (special rule for divide by 0, of course) and subtraction is the inverse of addition, so they have the same priority, so you're supposed to do stuff left to right in that case.

For example:
6 % 2 == 6 * (0.5) and
6 - 3 == 6 + -3

So, if you used PEDMAS on 6*2-3+5*2, you'd end up doing addition before subtraction, that is, (6*2)-(3+(5*2)) == -1, which is obviously not the same as 6*2-3+5*2 == (((6*2)-3)+(5*2)) == 19


No PEMDAS is not silly, it is a correct order of operation..




P Parentheses first
E Exponents (ie Powers and Square Roots, etc.)
MD Multiplication and Division (left-to-right)
AS Addition and Subtraction (left-to-right)

if you don't get the right answer following that, you are doing it wrong


#47 OP Hardcore Til I Die

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Posted 05 September 2012 - 18:06

It's 7. However, BODMAS and PEDMAS are both silly; Division is the inverse of multiplication (special rule for divide by 0, of course) and subtraction is the inverse of addition, so they have the same priority, so you're supposed to do stuff left to right in that case.

For example:
6 % 2 == 6 * (0.5) and
6 - 3 == 6 + -3

So, if you used PEDMAS on 6*2-3+5*2, you'd end up doing addition before subtraction, that is, (6*2)-(3+(5*2)) == -1, which is obviously not the same as 6*2-3+5*2 == (((6*2)-3)+(5*2)) == 19


No you wouldn't do addition before subtraction, that's only if you take the DMAS part too literally and don't understand the actual rules.

B
O
DM (left-to right)
AS (left-to-right)

is the correct order.

#48 +Xenosion

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Posted 05 September 2012 - 18:47

These types of open answer equations always make me rage at the stupidity of some people. Math is beautiful in that there is only one correct answer and if you don't have the correct answer, there is no explaining yourself. The idiots who sit there so assured of themselves with the wrong answer without a care just make me want to punch puppies.

#49 lt8480

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Posted 05 September 2012 - 21:03

No PEMDAS is not silly, it is a correct order of operation..

P Parentheses first
E Exponents (ie Powers and Square Roots, etc.)
MD Multiplication and Division (left-to-right)
AS Addition and Subtraction (left-to-right)

if you don't get the right answer following that, you are doing it wrong

No you wouldn't do addition before subtraction, that's only if you take the DMAS part too literally and don't understand the actual rules.

B
O
DM (left-to right)
AS (left-to-right)

is the correct order.


It's true that the order shouldn't be taken literally... but then again anyone who understands the logic really doesnt need PEDMAS or equivalent. Those who use PEDMAS (this thread is good proof) almost always seperate out Division before Multiplication and Addition before Subtraction. In fact I've seen it taught wrong so it's not very suprising so many people don't understand it.Luckily in this instance it works, but it would be interesting to give an equation that requires a thorough understanding of the order of operations.

#50 OP Hardcore Til I Die

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Posted 05 September 2012 - 21:12

It's true that the order shouldn't be taken literally... but then again anyone who understands the logic really doesnt need PEDMAS or equivalent. Those who use PEDMAS (this thread is good proof) almost always seperate out Division before Multiplication and Addition before Subtraction. In fact I've seen it taught wrong so it's not very suprising so many people don't understand it.Luckily in this instance it works, but it would be interesting to give an equation that requires a thorough understanding of the order of operations.


Well the fact that it has so many variants is a clue that the order of D/M and A/S isn't important :p

BIMDAS
PEMDAS
BODMAS
BIDMAS
PEDMAS

They're just acronyms used to help people remember the order. :p

#51 DPyro

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Posted 05 September 2012 - 21:55

BEDMAS

6-1x0+2/2
6-0+2/2
6-0+1
6+1
7

#52 cut

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Posted 05 September 2012 - 22:05

Posted Image

[/thread]

#53 *RedBull*

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Posted 05 September 2012 - 22:07

ok, what does 0 actually represent?

#54 evo0o

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Posted 06 September 2012 - 00:48

7, there is no other answer.

#55 Raa

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Posted 06 September 2012 - 01:27

7

How do I know? I used a calculator...

Can I get you to run that through a TI-85 and TI-86 please?

#56 Rohdekill

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Posted 06 September 2012 - 01:56

i guess for the result being 5 can only be:

6-1x(0+2)/2
6-1x(2/2)
6-(1x1)
6-1 = 5

can't see other way for that silly result lol


Actually, I think 5 came from following the steps EXACTLY in order:
6-(1x0)+2/2 (step 1: multiply)
6-0+(2/2) (step 2: divide)
6-(0+1) (step 3: addition)
6-1 (step 4: subtraction)
5

#57 LaP

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Posted 06 September 2012 - 14:52

I, for one, care whether people are able to solve a very basic arithmetic problem. It's representative of the overall level of numeracy.

But yes, it should never be written in such a way.


If you write a book about grammar but do not use any space between words, any punctuation, any paragraph and such would you complain that people don't get it ?

Yes knowing the order of operations is important and yes it's surprising that many people don't even know the basis.

But writing readable equations is as much important imo.

#58 OP Hardcore Til I Die

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Posted 06 September 2012 - 16:54

If you write a book about grammar but do not use any space between words, any punctuation, any paragraph and such would you complain that people don't get it ?

Yes knowing the order of operations is important and yes it's surprising that many people don't even know the basis.

But writing readable equations is as much important imo.


If it wasn't readable nobody would have got the answer!

#59 Pikey

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Posted 06 September 2012 - 18:41

Well , using my trusty slide rule , I get 8 ... near enough ..

oh , hang on a sec ...

#60 vetneufuse

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Posted 07 September 2012 - 01:02

Actually, I think 5 came from following the steps EXACTLY in order:
6-(1x0)+2/2 (step 1: multiply)
6-0+(2/2) (step 2: divide)
6-(0+1) (step 3: addition)
6-1 (step 4: subtraction)
5


seriously?

6-1X0+2/2

1X0 = 0

6-0+2/2

2/2 = 1

6-0+1

(6-0) = 6

6+1

(6+1) = 7

how hard is that? Add and subtract does not mean add then subtract, it meants do addition and subtraction in left to right order add or subtract doesn't have a precident, just do them left ot right therefore you get 6 minus 0 first...

the equation rewrites from 6-1x0+2/2 to this (6 - (1 x 0)) + (2 / 2)

additon and subtraction along with multiplication and division are treated at the same precident thats why you MUST do them form left to right...

I am just amazed how so many computer esc people can't grasp at such a simple concept