@Theo Poufinas OMG! Did You ever see Excel and Calculator? People please read all posts! You are so stupid!
I'm leaving this tread.
dude, don't make us stupid you should read this thread, my discussions from last night!
i also thought the correct answer is 288 but if ÷ means what i said, the answer for this poll is 2! start reading before telling me to read, and have some respect!
Quote ( Mikko Heikkinen @ April 15th 2011,09:17:09 )
Doesn't really matter do you use "÷" or "/", if you wanna present fractions you still should use the brackets to avoid inaccuracies
it does matter and is the thing that changes everything! notations in one line need to distinguish this things for faster typing but don't know how universal this rules are, but I know they exist and are applied in many ways!
Quote ( Mikko Heikkinen @ April 15th 2011,11:35:02 )
in a single line presentation the proper usage of brackets is necessary
or the differentiation notation between rational numbers and divisions!
Quote ( Brian Branch @ April 15th 2011,13:36:18 )
Simple fact. Both sides are inventing additional material into the equation to get their desired answer. One group are inventing the *, and the other side the extra ().
I am not inventing anything!
Quote ( Kevin Parkinson @ April 15th 2011,16:43:37 )
Your argument is nonsense. Division is division no matter what sign you use for it.
yes, division is division, but if you write math notations in a single line, you can differentiate rational numbers from division, because otherwise you will have to add brackets all over the place
Quote ( Marcelo Michelini @ April 15th 2011,16:53:24 )
but if you write math notations in a single line, you can differentiate rational numbers from division, because otherwise you will have to add brackets all over the place
You're right Marcelo, but the point I had issue with was...
Quote ( Theo Poufinas @ April 15th 2011,16:27:41 )
48÷2(9+3)=2 48/2(9+3)=288
This is just a different sign for division and makes no difference to the answer.
You do allude to what I have said all along though...
Quote ( Kevin Parkinson @ April 15th 2011,11:45:08 )
Simple fact is this would never be written in the form it is so as to avoid any confusion.
only proper reason to make 48÷2(9+3)=2 is that ÷ isn't the same with / which i think it is the same, but Marcelo proved by a photo that ÷ is different of / ... other reason is not proper, because you aren't allowed to do multiplication before dividing in our expression because 48:2 is before 2(9+3), ....don't know how to explain better in english
Quote ( Kevin Parkinson @ April 15th 2011,16:57:02 )
You do allude to what I have said all along though...
that is probablly correct but someone actually wrote this to confuse people, so here we are :p
Quote ( Kevin Parkinson @ April 15th 2011,16:57:02 )
This is just a different sign for division and makes no difference to the answer.
to me it does changes everything if it is /, then 48/2 is a rational number and so the unnecessary brackets would be like this (48/2)(9+3) if it is ÷, then the brackets would be like 48÷(2(9+3))
Quote ( Marcelo Michelini @ April 15th 2011,17:04:23 )
to me it does changes everything if it is /, then 48/2 is a rational number and so the unnecessary brackets would be like this (48/2)(9+3) if it is ÷, then the brackets would be like 48÷(2(9+3))
Again, why do you add an extra set of brackets which don't exist? Last time I checked the question was 48÷2(9+3)
48 ÷ 2 (12) Divisions comes first, as we go from left to right: = 24 (12) = 288
I can't believe some ignorant people are adding brackets, or multiplying first to get the answer they want. It's called ignorance, which is tragic.
1) It's a basic rule in math to go from left to right when both division and multiplication is involved in an equation.
2) A fraction is another way to write a division, I've shown evidence on a link at AboutMath.com
3) We have no brackets around the 2, stop adding!
4) Having a number infront of another number in brackets in the exact same as multiplying, there's no difference unlike some people like to create.
If you think the answer is 2, or any other than 288, you were not educated in a proper school.
I think my calculator is making a distinction whereby; 2*(9+3) is two functions but; 2(9+3) is one function. It's all part of the brackets, therefore this gets calculated first.
No idea if this is the correct way of doing it though :/
The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire statement and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it. You do NOT compute this expression from left to right until you use Algebra to simplify the statement 2(9+3).
So this can be rewritten as: 48 / (2*9 + 2*3)
Which leaves us with
48 / 24 = 2
Answer = 2.
Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 * (9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs.
It's got me convinced - especially the last bit in bold
The confusing part in the above calculation is how "16 divided by 2[2] + 1" (in the line marked with the double-star) becomes "16 divided by 4 + 1", instead of "8 times by 2 + 1". That's because, even though multiplication and division are at the same level (so the left-to-right rule should apply), parentheses outrank division, so the first 2 goes with the [2], rather than with the "16 divided by". That is, multiplication that is indicated by placement against parentheses (or brackets, etc) is "stronger" than "regular" multiplication.
I can bet all the money I have that the answer is 288.
So 48÷2(9+3)=???
- do what's inside of the brackets
48 ÷ 2 * 12 = ???
- ÷ and * have equal priority, so we perform ÷ as it is the leftmost
24 * 12 = 288
Saying that ÷ and / are different operations is utter bs. saying that a*b is not the same as ab is even more wrong.
They are the same thing. Do not let yourself be fouled by anyone who says the opposite. Call him incompetent and go away feeling superior.
Quote ( Kevin Parkinson @ April 14th 2011,23:56:35 )
Quote ( Kevin Parkinson @ April 14th 2011,22:57:42 )
Technically 2(9+3) should be calculated before 48 / 2 so the answer is 2.
If the question was 48 / 2 x (9+3) then the answer would be 288 but as the multiplication sign is omitted the 2(9+3) would be given priority, as if it was in parenthesis itself.
Quote ( Jonathan Seifort @ April 14th 2011,23:00:18 )
Makes no difference, a number before a bracket means the exact same as a multiplication sign.
Wrong!
Quote ( Theo Poufinas @ April 14th 2011,23:03:34 )
2(9+3) = 2*(9+3) -> same thing
Also wrong!
And the reason why I am correct is... Quote ( Slawek Waszkiewicz @ April 14th 2011,23:35:36 )
"Distributive property of multiplication over addition. Early Algebra problem.
The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire statement and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it. You do NOT compute this expression from left to right until you use Algebra to simplify the statement 2(9+3).
So this can be rewritten as: 48 / (2*9 + 2*3)
Which leaves us with
48 / 24 = 2
Answer = 2.
Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 * (9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs."
Well done Slawek!
I knew I was right and nice to see someone bothered to show why :)
As for distributative property, you must take the the whole 48 ÷ 2 inside brackets, you can not leave 48 out and take just two.
Quote ( Andrew Watson @ April 15th 2011,10:56:28 )
Why is it that if I put the equation (exactly as it was given) into my scientific calculator it gives the answer as 2? This agrees to my original method, but not to BEDMAS.
Your calculator has "Natural display"?
If it does, turn it off and then try again and see the answer...
Quote ( Andrew Watson @ April 15th 2011,18:15:40 )
It's got me convinced - especially the last bit in bold
But what about the B.E.D.M.A.S ?
You will find that the question is worded ambiguously like this on purpose. One, it's ambiguous because it's written on the computer, and two it's ambiguous because once you get past a certain grade you get taught implicit multiplication.
Basically, what implicit multiplication is multiplication by juxtaposition, or placing a number right next to each other. Most commonly used for variables, eg x * 12 becomes 12x.
However, you will find that implicit multiplication takes the same precedence as regular multiplication and division do. You still do it from left to right. For example,
Likewise for this example.
48 / 2(9+3) can be rewritten as 48 / 2 * (9+3)
because that's all implicit multiplication is. 12x = 12 * x, and likewise 2(9+3) = 2 * (9+3).
Also, BEDMAS, BODMAS, or PEMDAS, whatever you were taught. You are always taught to solve left to right, and that division and multiplication have the same precedence, and so do addition and subtraction.
And so, the equation is solved as follows: 48/2(9+3) 48/2(12) 24(12) 288