48÷2(9+3) = ????

[D3PART3D]

i was also taught that...
multiplication and division have equal rights...
addition and subtraction have equal rights....

+1

+1.

@Synthia: All you've done is proven that I'm smarter than Einstein!

[D3PART3D]

No it is just a short cut method of writing it

My teachers told me that too, but I'm sure it's wrong. They simplify it to make it easier to teach but in the process distort the facts.

FACTS.

I don't know what I'm talking about, actually. Please excuse the spam.

[Prime]

And here i thought maths are a pure and precise science.....

Google lies my calculator and computer told me

That my dear little overlong green grass blade is a serious allegation

Only if you put a comma in that sentence

http://www.stewartcalculus.com/data/def ... mpTold.pdf

[Stuart]

Code: Select all

http://www.stewartcalculus.com/

Listen to this guy. He sounds clever.

[RiaX]

2(9+3) makes the 2 part of the bracket and thus it takes priority over a standard multiply or division, the reason is you have to deal with the bracket first and you can do it by solving the bracket or expanding the bracket, either way the bracket is solved first.

You can solve that bracket in 2 methods

1) [2 x 12] , by solving the bracket first then dealing with its multiplication factor OR
2) [18 + 6], by expanding the bracket by the multiplication factor then doing the addition

also 2(9+3) = [(9+3) + (9+3)] = 24 which is the proper way of writing 2.(9+3)

so 48 / 2(9+3) is NOT equal to 48 / 2 x (9+3) but rather 48 / [(9+3) + (9+3)] as you can see they yeild two different results.

An easy way to show this is to substitute the numerals with letters for eg:

48 = y
2 = x
9 = z
3 = a

y / x(z+a)
y / [zx + xa] as you can see the bracket is solved first then insert your numerical values and the final anwser is 2

end of story

[Siemens]

The answer is 2. There's really no need for a whole thread about this unless you are uneducated or simply just trolling.
Kind Regards
Quantity Surveyor.

[Stuart]

The answer is 2. There's really no need for a whole thread about this unless you are uneducated or simply just trolling.
Kind Regards
Quantity Surveyor.

The Internet disagrees with you.
Kind Regards
Ignoramus

[Siemens]

The internet need educations

[Siemens]

The equation reads forty-eight divided by twice the amount of nine plus three. It does not read forty-eight divided by two; times the sum of nine and three.

[D3PART3D]

I can't believe it, but Siemens has just won the thread.

[Bladerunner]

You have to ask yourself, would someone posing this question have taken into account that by not putting a space (anywhere in the formula really), he/she is implying that it should read as you're assuming it should?

That's kind of a dumb comment. If the lack of space as Prime says means multiply it doesn't really matter what the asker is "implying." mathematical rules can't be ignored simply because the asker might be "implying" something.

I meant the lack of a space doesn't imply that the bracket forms part of the denominator.

[Bladerunner]

2(9+3) makes the 2 part of the bracket and thus it takes priority over a standard multiply or division

Wrong. There is no such rule.

a(b) = a * b

[Siemens]

See the division sign? See what's behind it?

[Bladerunner]

See the division sign? See what's behind it?

Still doesn't change a thing.

[Siemens]

it does, if 48 didnt want to be divided by the bracket , it should have said so

[Bladerunner]

it does, if 48 didnt want to be divided by the bracket , it should have said so

If it did want to, it should have said so: 48/(2(9+3))

[Siemens]

ah news flash... it does!!!

[Stuart]

I can't believe it, but Siemens has just won the thread.

Well done Siemens. You may just have earned yourself a custom title.

[Stuart]

See the division sign? See what's behind it?

No, I don't have a 3D screen. Should I get one? Will it help?

[jee]

in pink Rattie? *wicked grin*

[KALSTER]

From what I remember from high school maths and one year of varsity maths, the answer must be 2. The 2(9+3) counts as a single term just like 2x would be as an example. x is just = (9+3) in this case.

[Bladerunner]

An easy way to show this is to substitute the numerals with letters for eg:

x / 2 (9+3)

= x / 2 (12) [By BODMAS, simplify everything inside the bracket first]

= x / 12 * 2 [By the universally accepted rule that a(b) = a*b no nonsense that the 2 magically bonds with the bracket for no reason]

Now gentlemen, observe the ambiguity.

There is NO, and I mean NO reason whatsoever that would justify whether we should multiply or divide first. Without a bracket this cannot be determined. You can flaunt your titles (quantity surveyor, ooh aah) all you want, but you cannot justify your answer of 2 or 288 with mathematical certainty.

Sincerely,
Someone who actually knows math.

[Siemens]

Ooh! I'd love pink

[Stuart]

in pink Rattie? *wicked grin*

I like the way you think.



Actually, I'm a little nervous about the way you think. But that's another subject.

[Siemens]

From what I remember from high scool maths and one year of varsity maths, the answer must be 2. The 2(9+3) counts as a single term just like 2x would be as an example. x is just = (9+3) in this case.

Yes you are right.