6÷2(1+2)=?

Originally posted by MegaMind

Originally posted by knightseifer

but for 6÷2(1+2) , we cannot use 6÷2 as A

Sure you can! "A" can be any damn thing you want!!!

A ( B + C) = AB + AC

edit on 2-5-2011 by MegaMind because: (no reason given)

Yes, it can be any damn thing but not 6/2 in this question.
How can 6÷2(1+2) become 6(1+2)÷2 , you are changing the question..

Originally posted by GobbledokTChipeater

Originally posted by MegaMind

Originally posted by GobbledokTChipeater

Originally posted by MegaMind

this should be

15 * (1/3) * 4 * (1/2) * 7

It matters not. The answer is 70 either way.

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

6 * (1/(2(1+2))) = 1

good luck with that interpretation

Originally posted by ASeeker343

Originally posted by knightseifer


15÷3*4÷2*7 = 70

In this case, the question should be written as (6÷2)*(1+2) or 6(1+2)÷2, then we can have 6/2 as A

but for 6÷2(1+2) , we cannot use 6÷2 as A

Yes you can. 6÷2(1+2) is exactly equivalent to (6/2)(1+2) if the order of operations are followed correctly.

In order to get

6
------ you need an extra set of parentheses 6÷(2(1+2))
2(1+2)

You are adding those in on your own when you write it as this fraction. Thats bad math

You are adding bracket to 6÷2 as well.. it is not in the question.. 6÷2(1+2) and (6/2)(1+2) are different thing

I think we are wildly flagellating our minds on this problem.

First of all the OP didn't state this was a algebraic problem that required distributive properties.

Maybe we should agree not to treat it as such and go strictly with PEMDAS.

I feel we are over thinking this way too much and going overboard with something that should of been one page.

Originally posted by MegaMind

good luck with that interpretation

Why? I did the same as you. I changed the divide to a multiply, and then did 1/(denominator).

Exactly. Like. You.

The only difference is you believe the denominator to be 2, I believe it to be 2(1+2).

If my math is bad and i need luck to make it work, then so do you, because I copied.



.

Originally posted by knightseifer

Originally posted by MegaMind

Originally posted by knightseifer

but for 6÷2(1+2) , we cannot use 6÷2 as A

Sure you can! "A" can be any damn thing you want!!!

A ( B + C) = AB + AC

edit on 2-5-2011 by MegaMind because: (no reason given)

Yes, it can be any damn thing but not 6/2 in this question.
How can 6÷2(1+2) become 6(1+2)÷2 , you are changing the question..

No the equation is not changed at all 6/2 (1+2) = 6(1+2)/2 they are equivalent.

In fact these are all equal

6/2(1+2) = 6(1+2)/2 = 6/2 + 12/2 = 6(1/2 + 2/2) = (6 + 12)/2 = 9

Originally posted by knightseifer

You are adding bracket to 6÷2 as well.. it is not in the question.. 6÷2(1+2) and (6/2)(1+2) are different thing

If you correctly follow the order of operations they are the same thing.

I can add brackets to 1+2+3>>> 1+(2+3) and it doesnt have an effect on the expression.

Same with the above equation.

6÷2(1+2) >>> 6÷2(3) >>> 6÷2*3>>> NOT 6÷(2*3)

the fact that the 2 is directly adjacent to the parentheses does NOT mean that the multiplication takes precedence over the division

What would you do here?

6 ÷ 2 (1 + 2)(1 + 2)

----

My interpretation, and of course the correct one, is

6 * (1/2) * (1 + 2) * (1 + 2) = 6 * (1/2) * 3 * 3 = 27

-----------------

or what about?

6 ÷ 2 (1+2) ÷ 9

6 * (1/2) * (1+2) * (1/9) = 6 * (1/2) * 3 * (1/9) = 1

can't get it to link to google. copy and paste 6 ÷ 2 (1+2) ÷ 9 into google.

reply to post by MegaMind


Please tell me why my interpretation is wrong and yours is right, leaving aside the actual part up for discussion, of course.

You told me "good luck with that interpretation" and then didn't answer when I asked why and explained it's the same as yours except for our differences on what the denominator is, of course.

Originally posted by MegaMind

Originally posted by knightseifer

Originally posted by MegaMind

Originally posted by knightseifer

but for 6÷2(1+2) , we cannot use 6÷2 as A

Sure you can! "A" can be any damn thing you want!!!

A ( B + C) = AB + AC

edit on 2-5-2011 by MegaMind because: (no reason given)

Yes, it can be any damn thing but not 6/2 in this question.
How can 6÷2(1+2) become 6(1+2)÷2 , you are changing the question..

No the equation is not changed at all 6/2 (1+2) = 6(1+2)/2 they are equivalent.

In fact these are all equal

6/2(1+2) = 6(1+2)/2 = 6/2 + 12/2 = 6(1/2 + 2/2) = (6 + 12)/2 = 9

A÷B(C) = A÷BC
A
-----
BC

only if A ÷ B x C then
A
---- x C
B

* x = multiply

reply to post by GobbledokTChipeater


because you get the wrong answer of course. Thought that was obvious.

Originally posted by MegaMind
reply to post by GobbledokTChipeater

 

because you get the wrong answer of course. Thought that was obvious.

But your answer was only an "interpretation" too.

However I see you have reverted into the "I'm right, you're all wrong" mode.

If all you wanted to be was right, maybe you should be a primary school teacher ?!

reply to post by knightseifer


Many, many see it differently. This is like a language we agree certain words mean the same thing. I say 'cat' and u know what I mean. If u interpret a 'cat' to mean what I call a turtle then that is your problem. Your interpretation of what order you process 6/2(1+2) is simply wrong in light of many examples already shown here. Even the programmers at Google and many calculators say you are simply wrong.

This is exactly like beating a dead horse or banging my head against the wall. Interpret it your own way and when the other 99% disagree don't say I didn't warn you.

later - who said math wasn't fun

reply to post by MegaMind


Hi, can we still be friends?

I keep picturing the OP guy being held on some space ship and the aliens gave him this riddle to see if we were worthy of not blowing up.

The answer is 42, by the way. Always 42.

Originally posted by Cuervo
I keep picturing the OP guy being held on some space ship and the aliens gave him this riddle to see if we were worthy of not blowing up.

The answer is 42, by the way. Always 42.

LMAO I think we're all dead, then.

Sometimes one rule seems natural, and
sometimes another, so people will forget any rule we choose to teach
in this area. I've heard from too many students whose texts do "give
an example that really puts this rule to the test," but do so by
having them evaluate an expression like:

6/2(3)

that is too ambiguous for any reasonable mathematician ever to write.
And no matter what the rule, we would still constantly see students
write things like "1/2x" meaning half of x, so we'd still have to make
reasonable guesses rather than stick to the rules.

(My emphasis)

Link

I inputted the OP's equation in three different calculators and got 6/2(1+2) = 1.
On the other hand, my phone gave me this: 6/2*(1+2) = 9.
There seems to be a rule, only implemented in some devices, that gives precedence to a digit adjacent to a bracket. The calculator on my phone doesn't allow the omission of a * (multiply) sign and comes up with a different result.
Machines disagree; teachers disagree. Cockerels can be pulled out and measuring tapes unwound but, unless those who teach maths and those who program calculating machines agree with each other and among themselves, the oners and the niners will go on bickering until the cows come home.

Personally, I think the answer is 42.
Cuervo beat me to it.

First use the standard "/" to substitute for division... this makes the equation a fraction:

6/2(1+2). So now the 6 would be divided by the result of the denomimator, which is 2(1+2) which is 6, so 6/6=1

Originally posted by Hoosyourdaddyo
First use the standard "/" to substitute for division... this makes the equation a fraction:

6/2(1+2). So now the 6 would be divided by the result of the denomimator, which is 2(1+2) which is 6, so 6/6=1

Now...if the equation was changed to 6/2*(1+2) the answer is 9. The reason is that the multiplying sign divides the equation into 6/2*(3)=3*3=9

wow im in shock...

17 pages for such a simple math equasion... Christ i even know the answer....

come on people