Math quiz;


zaren

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#1
6/2(1+2) = ?
 

nitewalk

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#5
zaren said:
6/2(1+2) = ?
The answer is inconclusive.

The two answers are 1 and 9. The problem lies in the insufficient brackets used, therefore arising in the inconclusiveness. By dividing 2 first, you would get the answer 9. However, if you take the division as a fraction, you would get 1.

Therefore a proper rigourous way to present this is to make a distinction between (6/2)*(1+2) and 6/(2(1+2)). The former gives 9 while the latter gives 1.

As such, different brands and models of calculators give a different answer.
 

ricohflex

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Feb 24, 2005
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#7
Order of operations

The order of operations is the order in which all algebraic expressions should be simplified.

1st order Parentheses or brackets as we call it here in Singapore
2nd order Exponents (and Roots)
3rd order Multiplication & Division
4th order Addition & Subtraction

Answer is 1.
 

Last edited:
Sep 17, 2008
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#8
Order of operations

The order of operations is the order in which all algebraic expressions should be simplified.

1st order Parentheses or brackets as we call it here in Singapore
2nd order Exponents (and Roots)
3rd order Multiplication & Division
4th order Addition & Subtraction

Answer is 1.
boh leh.

once you bracket, you end up with

6/2(3). depending on how you take 2(3) to mean. if its just 2*3, normal order takes place.

but if you view as (2*3), its 1. i took the first.
 

nitewalk

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#9
It depends on how you interpret the expression. Like i mentioned, it is incomplete. Neither are wrong. We always think that mathematics is a strictly right or wrong discipline, but right or wrong depends on the way it is expressed.
 

zaren

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#11
best answer from the net....

6÷2(1+2)=?

Team 9: “THE ANSWER IS 9”
Those who argue that the answer is 9 follow standard order of operations:
6/2(1+2)
First you do whatever is in the parentheses which is (1+2):
6/2(3)
Next, you do multiplication and division in order from left to right, so you divide 6 by 2 and then multiply the result by 3. The parentheses are not needed as 2(3) only indicates 2x3:
3(3) = 9

Team 1: “THE ANSWER IS 1”
Those who argue that the answer is 1 follow order of operations, but accept that multiplication by juxtaposition indicates that the juxtaposed values must be multiplied together before processing other operations:
6/2(1+2)
First you do whatever is in the parentheses which is (1+2):
6/2(3)
Next you must do 2(3) because multiplying by just putting things next to each other (multiplication by juxtaposition), rather than using the "x" sign indicates that the juxtaposed values must be multiplied together before other operations.
6/6 = 1

As I have demonstrated here both answers can be argued for and the problem lies with what your view on “multiplication by juxtaposition” is:
Whether or not you believe 6/2(3) is different than 6/2x(3)
From what I’ve been able to find, there is no definitive answer or consensus on this matter (even different calculators will calculate them differently), Therefore it is up to the one writing the expression to clearly indicate what he means without any ambiguity by writing:

6/2x(1+2) or 6/(2(1+2))

In conclusion I would like to state that the person who wrote the expression 6/2(1+2) is an absolute !@#$-headed !@#$% who does not know how to make it clear what he means and just likes !@#$%^& people off. Learn some math !@#$!
Source(s):
my super smart and sexy gf

LOL!!
 

nitewalk

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#13
zaren said:
best answer from the net....

622(1+2)=?

Team 9: “THE ANSWER IS 9”
Those who argue that the answer is 9 follow standard order of operations:
6/2(1+2)
First you do whatever is in the parentheses which is (1+2):
6/2(3)
Next, you do multiplication and division in order from left to right, so you divide 6 by 2 and then multiply the result by 3. The parentheses are not needed as 2(3) only indicates 2x3:
3(3) = 9

Team 1: “THE ANSWER IS 1”
Those who argue that the answer is 1 follow order of operations, but accept that multiplication by juxtaposition indicates that the juxtaposed values must be multiplied together before processing other operations:
6/2(1+2)
First you do whatever is in the parentheses which is (1+2):
6/2(3)
Next you must do 2(3) because multiplying by just putting things next to each other (multiplication by juxtaposition), rather than using the "x" sign indicates that the juxtaposed values must be multiplied together before other operations.
6/6 = 1

As I have demonstrated here both answers can be argued for and the problem lies with what your view on “multiplication by juxtaposition” is:
Whether or not you believe 6/2(3) is different than 6/2x(3)
From what I’ve been able to find, there is no definitive answer or consensus on this matter (even different calculators will calculate them differently), Therefore it is up to the one writing the expression to clearly indicate what he means without any ambiguity by writing:

6/2x(1+2) or 6/(2(1+2))

In conclusion I would like to state that the person who wrote the expression 6/2(1+2) is an absolute !@#$-headed !@#$% who does not know how to make it clear what he means and just likes !@#$%^& people off. Learn some math !@#$!
Source(s):
my super smart and sexy gf

LOL!!
Similar answer as i've stated. I had discuss this before with a maths lecturer at a local university and he confirms that the answer is not conclusive at all. Even many secondary school maths teachers will get this wrong.
 

BBTM

Senior Member
Nov 23, 2004
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#14
If the / is --- (over), ans is 1 to me. But / is /, is 9.

6 --- 2(2+1) = 1
6/2(2+1) = 9

For me, see how the divide is drawn. :D
 

nitewalk

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#16
bonrya said:
Brackets first. Ans is 1. Ask my a math teacher mrs Ang pls. :bsmilie:
Like i said, even experienced maths teachers get it wrong. If there is insufficient bracket, the expression will lead to different answers. Both interpretations are not wrong (note: i didn't use the word "correct"), most teachers would have you to believe their interpretation is right, because even teachers will think there is only right and wrong in maths.

Some secondary school teachers teach students that the gradient of a vertical line is "infinity", yet they are wrong. Thus, be discerning.
 

Sep 17, 2008
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#17
cannot say liddat. how expect secondary school kids to learn advanced stuff? must slowly build up what.

machiam we learn f=ma. then become f=dp/dt. then suddenly end up with einstein relativity for motion... must be realistic also...

so telling kids gradient of vertical line is "infinity" is suitable at that point in time lor...

anyways, qn psoted by ts, proves that the person who wrote it made a mistake only haha
 

nitewalk

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#18
allenleonhart said:
cannot say liddat. how expect secondary school kids to learn advanced stuff? must slowly build up what.

machiam we learn f=ma. then become f=dp/dt. then suddenly end up with einstein relativity for motion... must be realistic also...

so telling kids gradient of vertical line is "infinity" is suitable at that point in time lor...

anyways, qn psoted by ts, proves that the person who wrote it made a mistake only haha
Conceptually, it is wrong. Because infinity is not a number, it is more of a concept of massiveness that cannot be stated in numerical terms. More technically, infinity and undefined are actually different and indeterminate is yet another concept which differs from the previous two.

Whatever i said above, can be comprehended by secondary school students, simple analogy suffice. I was just making a point to bonrya to think critically and beyond what he is told. Learning goes beyond passive acceptance of what is told to us.
 

Last edited:
Sep 17, 2008
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#19
Conceptually, it is wrong. Because infinity is not a number, it is more of a concept of massiveness that cannot be stated in numerical terms. More technically, infinity and undefined are actually different and indeterminate is yet another concept which differs from the previous two.

Whatever i said above, can be comprehended by secondary school students, simple analogy suffice. I was just making a point to bonrya to think critically and beyond what he is told. Learning goes beyond passive acceptance of what is told to us.
bonnie was kidding,. and she's a she. not a he...
 

nitewalk

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#20
allenleonhart said:
bonnie was kidding,. and she's a she. not a he...
Oh lol. Oops. Sorry. The problems of the cyber world :p
 

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