48÷2 (9+3) argument

cbrunsdonza said:
You should see the other forums I'm currently reading on this issue. To top it all in SA we say BODMAS and some other countries its BIDMAS! You wanna see the flameing just on that issue
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cbrunsdonza said:
Do you read it as 48÷2(9+3) or mentally do you see it as 48÷2x(9+3)?
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It's the same thing! If there is nothing between the bracket and a number, it means multiply. In mathematics, a . is often used to indicate multiplication. It could therefor be written as 48/2.(9+3)

I finished engineering mathematics at University, if that means anything. This, however, is something you learn in grade 8 at school, if I remember correctly.
 
Keeper said:
Mike, that sum you posted up there would be valid if it were 48/(2(9+3))......but it's not.

The question is 48/2(9+3)

48/2(9+3) = 48/2*12 = 24*12 = 288
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There's your mistake ;) It should be 24/12, not 24*12.

Refer to post above, you can't add brackets to individual expressions within the equation.
 
Viva said:
It's the same thing! If there is nothing between the bracket and a number, it means multiply. In mathematics, a . is often used to indicate multiplication. It could therefor be written as 48/2.(9+3)

I finished engineering mathematics at University, if that means anything. This, however, is something you learn in grade 8 at school, if I remember correctly.
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Viva for President!!
 
Viva said:
I finished engineering mathematics at University, if that means anything.
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Here you go :D

noddy-badge1.jpg


Now let's not turn this into a penis argument about who's more qualified because engineering maths sits somewhere around the middle of the pile :P I once tutored 3rd year engineering students who didn't know what a set is :wtf:
 
Ekstasis said:
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)

brackets first (9+3) =12
MD - LEFT TO RIGHT

so first 48/2 =24
then 24x12 =288
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Actually you hit it on the nail but your interpretation of parentheses is wrong here. Always keep in mind with parentheses that while we are taught 2(9+3) is 2x(9+3), the multiplication that is indicated by placement against parentheses is stronger than regular multiplication and/or division.
 
Viva said:
It's the same thing! If there is nothing between the bracket and a number, it means multiply. In mathematics, a . is often used to indicate multiplication. It could therefor be written as 48/2.(9+3)

I finished engineering mathematics at University, if that means anything. This, however, is something you learn in grade 8 at school, if I remember correctly.
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Dude, Standard 6 was many moons ago for me, 1989, thats why I redid my High School maths at UNISA. And yes I do agree the real number in front of the parenthesis implies multiplication but immediately to the values inside the parenthesis/brackets.

(The reason why I redid my maths was because I sucked at geometry but loved algebra)
 
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288, BODMAS from High School Higher Grade Maths (actually it starts in grade 7)
 
Mike Hoxbig said:
There's your mistake ;) It should be 24/12, not 24*12.

Refer to post above, you can't add brackets to individual expressions within the equation.
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sure you can....

4*2 + 1 is the same as (4*2) + 1


The point is there is a "*" between the 2 and the bracket, therefore you solve from left to right

the multiplication between the brackets takes no precidence over division, if it does, please show me this rule.
 
the multiplication that is indicated by placement against parentheses is stronger than regular multiplication and/or division.
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There is no such rule.
 
Keeper said:
sure you can....

4*2 + 1 is the same as (4*2) + 1


The point is there is a "*" between the 2 and the bracket, therefore you solve from left to right

the multiplication between the brackets takes no precidence over division, if it does, please show me this rule.
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Division takes precedence over multiplication but we need to decide when we determine the divisor if we give precedence to the parenthesis multiplier or not. I've been taught at both school and UNISA that the parenthesis multiplier takes precedence.
 
Keeper said:
sure you can....

4*2 + 1 is the same as (4*2) + 1


The point is there is a "*" between the 2 and the bracket, therefore you solve from left to right

the multiplication between the brackets takes no precidence over division, if it does, please show me this rule.
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But the 2 forms part of the brackets expression, which is why the statement is as I drew it above.

Do some reading people.

Simplify 16 ÷ 2[8 – 3(4 – 2)] + 1.

16 ÷ 2[8 – 3(4 – 2)] + 1
= 16 ÷ 2[8 – 3(2)] + 1
= 16 ÷ 2[8 – 6] + 1
= 16 ÷ 2[2] + 1 (**)
= 16 ÷ 4 + 1
= 4 + 1
= 5
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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".
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Note how 16 ÷ 2[8 – 6] is reduced to 16 ÷ 4. That is because the 2 is part of the brackets. If we did it your way, then 16 ÷ 2 would be evaluated first.
 
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Thanx mike, now you've just confused the 5hit out of me...

Google doesn't fking lie!



but yeah, you might actually be right on this I think....
 
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