48÷2(9+3)

[Rodp]

Originally Posted by jonesyedxr6

Up to the stage of

a
---
b(c+d)

is all well and fine, but once (c+d) are added to make say 'e' you are left with

a
---
be

or

a
-- * e
b

which is exactly the same as

a ÷ b * e

- Just because the 'b' and 'e' can be written under the 'a', does not mean that they are multiplied first.

You must have done a completely different strain of Mathematics than I did.

a is the numerator

b(c+d) is the denominator.

[XRGhia]

gotta love a friday arvo mind****..



my answers 288.....

[Rodp]

Originally Posted by jonesyedxr6

incorrect.

If you want to expand like you demonstrated above ie. a(b+c) = ab + ac then you have to do it this way

48 ÷ 2(9+3)

= (48/2) * 9 + (48/2) * 3

= 216 + 72

= 288

a(b+c) = (ab + ac)

[thefargo]

bedmas, where e is exponents

the b is first which means deal with the brackets, and get rid of them.
in the brackets is 12. to get rid of them you have to multiply by 2 = 24.
now you have dealt with the brackets!
the problem is now 48 divided by 24.
calculators are not always correct, it depends on the order of operations that may be unique to the calculator

[SEZ213]

Google says 288,
Casio Graphics Calculator says 288
TI86 says 288,
Sony xperia X10 says 288.
Excel says 288

Now, five out of five say 288...hrmmm...I wonder.

The reasoning that two doesn't factor in to the answer is because of the layout. The layout given, is the way you work it out.

The fact there is no 'x' doesn't weigh into it at all as:

Multiplication can be written three different ways:

9 * x
9x
9(x)

http://library.thinkquest.org/20991/prealg/eq.html

division or multiplication are answered in order of which comes first (left to right).

[thefargo]

ok sezzy, try it on the graphics calculator that has had the order of operations programmed properly, ie one of the latest.
give a casio fx-9890GAU plus a go. it's got the most up to date chip in it.
btw it says

2

[MITCHAY]

Originally Posted by Sezzy

Yep, that works too.

Glad someone understood me

[XD 351 Ute]

I ran out of fingers and toes at 20.......

Ed

[SEZ213]

Originally Posted by thefargo

ok sezzy, try it on the graphics calculator that has had the order of operations programmed properly, ie one of the latest.
give a casio fx-9890GAU plus a go. it's got the most up to date chip in it.
btw it says

2

When did order of operations change? There is no 'properly' about it...there is only one order of operations.

Originally Posted by MITCHAY

Glad someone understood me

Basic code!

[jonesyedxr6]

Originally Posted by Rodp

You must have done a completely different strain of Mathematics than I did.

a is the numerator

b(c+d) is the denominator.

yeah probably because what i said there is wrong sorry, only because i started with the wrong thing tho, it's not

a
---
b(c+d)

it's actually

a
- * (c+d)
b


which simplifies to

a(c+d)
------
b

substitute values a, b, c, d;

= 288

[thefargo]

[QUOTE=Sezzy]When did order of operations change? There is no 'properly' about it...there is only one order of operations.

no argument there, but calculators don't always agree, hence the post a few pages back, with two different models of calc showing two different answers.

my point, probably poorly made, was that the order of operations built in to the calc, isn't always correct, once again look at the TI a few pages back.

this is similar to problems that my students have when playing with exponents and roots, the calc is not always correct.

at the end of the day it is a poorly written problem

[Rodp]

Originally Posted by jonesyedxr6

yeah probably because what i said there is wrong sorry, only because i started with the wrong thing tho, it's not

a
---
b(c+d)

it's actually

a
- * (c+d)
b


which simplifies to

a(c+d)
------
b

substitute values a, b, c, d;

= 288

Refer to post #95.

[burkie_21]

jus started ww3 in my house. my answer is 288

[Rodp]

FWIW, a case can be made for both answers IMO.

It's just a poorly stated function designed to raise debate.

[Iggypoppin']

[QUOTE=thefargo]

Originally Posted by Sezzy

When did order of operations change? There is no 'properly' about it...there is only one order of operations.

no argument there, but calculators don't always agree, hence the post a few pages back, with two different models of calc showing two different answers.

my point, probably poorly made, was that the order of operations built in to the calc, isn't always correct, once again look at the TI a few pages back.

this is similar to problems that my students have when playing with exponents and roots, the calc is not always correct.

at the end of the day it is a poorly written problem

It is written poorly for a reason, as far as I can remember it is an equation designed to determine how a person will solve it. Baby boomers appear to solve 48/2(9*3)=x as x=2 and for gen Y it is x=288. the different methods taught at corresponding age levels proves that one generation was taught X and another Generation was taught Y.
The equation itself is very straightforward depending on your education of these typical equations and it is the way it is written that causes such arguments.
There are exceptions to the rule of course. My own findings from asking my work mates show that of 28 employees, 17 are baby boomer, 2 are X, and 9 are gen Y. 11 of the 17 flunked school and could not answer the question, the other 6 answered 2. The X gen both flunked and could
not answer. Half the gen Y answered "who cares" with various expletives, the other half answered 288.

[Michael_F90]

Its 2 dammit!

Bimdas - so brackets first x 2 divide by 48 = 2

The calculators give 288 because to get it right on a calculator you need to put the brackets in so its 48/(2(9+3)) then you will get 2. This is because the brackets mean multiply whatevers inside by whatever is outside and we all know multiplication comes before division.

If the answer were 288 it would be written like:
(48/2)(9+3)
But its not so the answer is two!

[jonesyedxr6]

Originally Posted by Rodp

Refer to post #95.

yourself.

i will space it out for you shall i? - your wolfram or whatever is wrong (probably only because it doesn't understand correctly tho)

a
- * (c + d)
b

=

a...(c+d)
- x-----
b...1

(when multiplying fractions; numerator times numerator, denominator times denominator)

=

a(c+d)
------
b*1

=
a(c+d)
------
b

[jonesyedxr6]

I think i'm enjoying this too much!

[NC1183]

Originally Posted by ST

To work it out correctly you isolate the two equations and then multiply them together:

48/2 = 24
9+3 = 12
24*12 = 288

Logical, (much more) simple and also correct.

Where is everyone getting TWO equations from, it is a single line equation.

x=48 / 2 x ( 9 + 3)



By the way, the three scientific calculators, which didn't fail me in either my HSC, or two trade certificates (Lineworker and Electrician) say the answer is 2. Calculators are, Casio FX-82, Casio FX -100AU and a Sharp EL-531RH

[MITCHAY]

Originally Posted by jonesyedxr6

I think i'm enjoying this too much!

Lol yeah I've been getting into it too, it's interesting. You can see how each side gets their answer but look anywhere on the net and there is no conclusive answer :

For the record what Flappy said in response to Geez Louise's Excel demo, if you put =SUM(48/2(9+3)) it actually results as a formula error and proposes =SUM((48/2*(9+3)) as a correction which = 288 . Well in my version it does anyway

[SEZ213]

Originally Posted by Michael_F90

Its 2 dammit!

Bimdas - so brackets first x 2 divide by 48 = 2

The calculators give 288 because to get it right on a calculator you need to put the brackets in so its 48/(2(9+3)) then you will get 2. This is because the brackets mean multiply whatevers inside by whatever is outside and we all know multiplication comes before division.

If the answer were 288 it would be written like:
(48/2)(9+3)
But its not so the answer is two!

Not quite.

The BIMDAS,BODMAS,BOMDAS,PEDMUS, whatever discussion all works around one principle. You work from left to right. The order of calculating the multiplication or division is dependent on where it falls, left to right.

So for the equation above the working out is as follows:

48/2(9+3)

Brackets always comes first

So 48/2(12).

Next order of operation working left to right is 48/2

So 24(12)

extrapolated to 24x12 if you wish, totalling 288.

Originally Posted by thefargo

no argument there, but calculators don't always agree, hence the post a few pages back, with two different models of calc showing two different answers.

my point, probably poorly made, was that the order of operations built in to the calc, isn't always correct, once again look at the TI a few pages back.

this is similar to problems that my students have when playing with exponents and roots, the calc is not always correct.

at the end of the day it is a poorly written problem

I don't know that I'd say it's poorly written, all mathematical equations are able to be interpreted two or more ways. The understanding of the principles surrounding mathematics is the key IMO anyway.

I saw the TI comparison, and had a small giggle to myself to be honest.

[NC1183]

Originally Posted by Iggypoppin'

why would you split one equation ( 48/2) and create two new ones (2*9, 2*3) when the bracketed digits are obviously solved first before continuing the equation as written...?

Originally Posted by ST

To work it out correctly you isolate the two equations and then multiply them together:

48/2 = 24
9+3 = 12
24*12 = 288

Logical, (much more) simple and also correct.

Originally Posted by jonesyedxr6

incorrect.

If you want to expand like you demonstrated above ie. a(b+c) = ab + ac then you have to do it this way

48 ÷ 2(9+3)

= (48/2) * 9 + (48/2) * 3

= 216 + 72

= 288

I did it that way, as i was always taught, by 6 different teachers of the mathematics profession that, any number or numbers inside a set of brackets is multiplied by the numeral directly outside the brackets as an individual, ie a(b + c) = a*b + a*c.

[Iggypoppin']

Wierd...I never learnt it as such. Rather to seperate the equation into two and go from there.

[NC1183]

Originally Posted by Iggypoppin'

Wierd...I never learnt it as such. Rather to seperate the equation into two and go from there.

In which case, you would separate it as

48
---------
2( 9 + 3)

[shedcoupe]

Perhaps the only way to settle this is to give it to some 'idiot savants'.
I'm a bit (or a lot) Asperger-ish, but not anywhere near the level required ....

Or, Sheldon from Big Bang Theory, are you listening ???

[Coogs289]

48/2(9+3)=288
48/(2(9+3))=2

[Iggypoppin']

Originally Posted by NC1183

In which case, you would separate it as

48
---------
2( 9 + 3)

no, it would be written thus
(9+3)=12
48/2=24
product of equation one(9+3) and equation two 48/2 is 24 x 12.
I seperate the equation enclosed in the brackets, solve it, then solve the remaining equation of 48/2 and create the product of the two being 288.

[noosacuda]

When i was a t school,(when Jesus played fullback for the Israelites,) we'd have read it like 48÷2(9+3) ........ 9+3=12 (brackets first). 2x12=24.(a number outside the brackets has a "silent" Multiplication sign, then
48 divided by 24, Therefore, =2

[Racecraft]

B rackets
O f
M ultiplication
D ivision
A dd
S ubract


or for the young engineering type maths2 students

B rackets
E xpontent
M ultiplication
D ivision
A dd
S ubract

The 'E' and 'O' are the same

The answer as it is written in the Op is 288

Originally Posted by Geez Louise

Maybe we should send this into SBS - Letters and numbers show... and get Lily to solve it!

and by the way...if you pop it into Excel as =sum(48/2(9+3) you get....288.

You left out the second bracket :P

EDIT: excel is a cheater because you have to add an extra bracket @ the start of the sum for a firmula to be written..........

[Iggypoppin']

I still don't understand how people are missing the 24x12 part...