48÷2 (9+3) argument

So people honestly think that 48÷2(12) is not equal to 48÷2*(12)
Thats the only way you can get 2 as your answer to the equation in the OP
 
HapticSimian said:
I think this sufficiently illustrates the banality of this exercise:
16h6ja8.jpg


plifying and solving different algebra problems. Without it, two different people may interpret an equation or expression in different ways and come up with different answers. The Order of Operations is:
  1. Parentheses and Brackets -- Simplify the inside of parentheses and brackets before you deal with the exponent (if any) of the set of parentheses or remove the parentheses.
  2. Exponents -- Simplify the exponent of a number or of a set of parentheses before you multiply, divide, add, or subtract it.
  3. Multiplication and Division -- Simplify multiplication and division in the order that they appear from left to right.
  4. Addition and Subtraction -- Simplify addition and subtraction in the order that they appear from left to right.

Which leads to:
48 ÷ 2 * (9+3)=
48 ÷ 2 * (12)=
48 ÷ 2 * 12=
24 * 12=
288
Click to expand...

I find it interesting that the "upgraded" model of each calculator equates 2, while the lower models equate 288. But 288 seems to be right, logically following the rules of algebra.

I suppose I have a prejudice to see 48 / 2 * (9+3) as being different to 48 / 2(9+3). In the former, I would have no problem simply using BODMAS and going from left to right, but in the latter, I want to treat 2(9+3) as a single term and simplify it fully before dividing, which is wrong according to the rules you posted.

Edit: Bah! I'm still not convinced that 288 is the right answer! :confused:
 
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The expression is badly written and open to interpretation. There isn't a correct answer. A mathematician wouldn't write it like this.
 
Archer said:
Show me that rule...
I never got taught anything about juxtaposition taking precedence over division/multiplication.
Click to expand...

Well think logically:

If we replace (9+3) with x we'll get:
48÷2x

Then it should be simple right?
 
Qwikslver said:
Well think logically:

If we replace (9+3) with x we'll get:
48÷2x

Then it should be simple right?
Click to expand...

Yip
48÷2x
=24x
=288 (if x = 12)

(BODMAS, left to right...)
There are no hard coded rules for implied operations, which is why in situations such as this, just follow BODMAS to the letter. Dont confuse things with implied operations. Math isnt built to handler implied stuff at all, so you take stuff at face value
 
Archer said:
Show me that rule...
I never got taught anything about juxtaposition taking precedence over division/multiplication.
Click to expand...

Distributive rule a (b + c) = a*b + a*c

When we are adding and multiplying with a parenthesis, we distribute the multiplication through the addition.
 
Barilak said:
Only what's inside the bracket.
Click to expand...

What do you do in case you have unlike terms inside the brackets ? :erm:

Remember the example given is a simple arithmetic sum with only numbers but you might have a problem once you start working with variables.
 
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Argh... :D

Let a=48, b=2, x=9, y=3, z=a÷b

a÷b(x+y) = z(x+y)
The fact that this is 100% correct blows you guys out of the water

But lets use the distributive law...
You will get....
a÷b*x+a÷b*y
=24*9 + 24*3

The end. Or do people not remember what constitutes a single term?
 
At the end of the day, this is all just pissing in the wind. This equation can be interpreted as

48
--- (9+3)
2

or

48
----
2(9+3)

As far as I can tell, both of these interpretations are legal. Which is why mathematicians use fraction notation.
 
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Let's just all agree that it's a crap way of writing an equation in the first place. Life is too short to get hung up on sh*t like this.
 
Archer said:
Argh... :D

Let a=48, b=2, x=9, y=3, z=a÷b

a÷b(x+y) = z(x+y)
The fact that this is 100% correct blows you guys out of the water

But lets use the distributive law...
You will get....
a÷b*x+a÷b*y
=24*9 + 24*3

The end. Or do people not remember what constitutes a single term?
Click to expand...

Have you forgotten about BODMAS now? How can you do division before brackets ?
 
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