48÷2(9+3) = ?

Original post by lalilou

48÷2(9+3)
The fact that there are brackets there means that the 2 is paired up to the (9+3).

This isnt correct. 2(9+3) is the same as 2*(9+3)

the 2 would be paired with the (9+3) if it was (2(9+3))

Reply 522

jit987

The answer '2' is winning! yepeee!

Reply 523

CameraGirl

Original post by connor ellis

This isnt correct. 2(9+3) is the same as 2*(9+3)

the 2 would be paired with the (9+3) if it was (2(9+3))

all three things you just wrote are exactly the same hehe

Reply 524

ok this is different to the original thread. ÷ is different to /
/ implies brackets wheras ÷ does not. with the / the answer is 2
with ÷ the answer is 288

Reply 525

timiop2008

1

Original post by Simplicity

Sorry, but some people at the Maths computer cluster was arguing about this.

I say it's 2.

THE ANSWER IS 2. I WILL TRY AND EXPLAIN WHY HERE:

The key to answering this answer correctly is knowing the "distributive law", sometimes called the "distributive property". Most calculators including google's are not advanced enough to consider the distributive law - this is why your calculator may be giving you the incorrect alternative of 288.

In the problem: 48÷2(9+3), you have to think of the 2(9+3) as ONE SINGLE ENTITY i.e. you cannot break this up. This is due to what mathematicians call the "distributive law" or "distributive property" - google it for more info.

Applying the distributive law, the problem 48÷2(9+3) becomes:
48÷(2(9+3))
From here, the problem becomes as straightforward as most people probably thought it was initially:
48÷(2(12))
=48÷(24)
=48÷24
=2

The people who are answering the incorrect answer of 288 are doing this:
48÷2(9+3)
=24(9+3)
=24x12
=288 = WRONG
This is incorrect because this solution does not obey the distributive law. It splits up the unbreakable entity '2(9+3)'. into 2 and (9+3). You cannot do this.

Reply 526

Original post by CameraGirl

all three things you just wrote are exactly the same hehe

seperatly they are, however, when placed back into the original equation they are not.
48÷2(9+3) is different to 48÷(2(9+3))
what stems from this is that if the 2 is not paired with the (9+3) then the answer is 288 using the rule of working from right to left.
48÷(2(9+3)) this is 2
48÷2(9+3) = 288 IMO

Reply 527

Triple_H

Original post by connor ellis

ok this is different to the original thread. ÷ is different to /
/ implies brackets wheras ÷ does not. with the / the answer is 2
with ÷ the answer is 288

The division sign is exactly the same as /.

If you look at ÷ it is a dot a line then a dot, implying dot 1 is the thing above the line and dot 2 is below the line.

Reply 528

maths134

So like why has this been discussed for 24 pages ? and its 2

Reply 529

Original post by timiop2008

This is incorrect because this solution does not obey the distributive law. It splits up the unbreakable entity '2(9+3)'. into 2 and (9+3). You cannot do this.

(2(9+3)) is an 'unbreakable entity'

2(9+3) is simply the same as 2*(9+3)
in the context of the original equation....

Reply 530

CameraGirl

Original post by timiop2008

distributive law

this is what i've been trying to say haha, but didn't realise it had a name, and i'm not that great at explaining haha. thank you :smile:

Bidmas ffs.

http://www.facebook.com/home.php?sk=question&id=10150144688502127

Poll. Ask away. Added options for it being undetermined and ambiguous

Reply 533

timiop2008

1

Original post by fwed1

http://www.wolframalpha.com/input/?i=%2848%2F2%29%289%2B3%29

Just posting this link that I do not believe has been posted before. As you can see in my search term I entered brackets however wolfram took the first set away as they were not needed leaving the answer in the format given by the question. Therefore people can assume that we are working with (48/2)(9+3).

For further reference here is what it would be like if we had 48/(2(9+3))

http://www.wolframalpha.com/input/?i=48%2F%282%289%2B3%29%29

As you can see the question has been set out differently.

288 is given in the top correct link
2 is given in the bottom incorrect link.

That is all.

The correct answer is 2. You cannot make the original expression equal to the expression: (48/2)(9+3). You cannot do this because the distributive law does not allow it. According to the distributive law, you have to consider (2(9+3) as an unbreakable entity.

Reply 534

ily_em

17

Why has nobody closed this thread yet? :colonhash:

Reply 535

wer343lit

11

Original post by MathematicsKiller

HAHAHAHAHAHAHAHAHAHAHAHA!!!!!!!!!
This is the most ridiculous thread I have seen in a long time!!!!!

Whoever disagrees with 2 as the answer needs to start school all over again from Pre-GCSE years.

BIDMAS, then working from left to right gives 288 as the answer.

:s-smilie:

To get 2 as the answer, you need to assume things about the position of the 2 which we cannot be sure of from the form the equation is written in.

Reply 536

timiop2008

1

Original post by MostCompetitive

BIDMAS:

Brackets
Indicies
Division
Multiplication
Addition
Subtraction

Therefore, it is simply:

\frac{48}{24} =2

Haha. I love the way you have considered such a challenging question in such simplistic terms but you have actually got the correct answer. Well done lol

Reply 537

Original post by MostCompetitive

BIDMAS:

Brackets
Indicies
Division
Multiplication
Addition
Subtraction

Therefore, it is simply:

\frac{48}{24} =2

Bidmas is misleading. division and multiplication are on the same level of priority.
as they have equal priority to decide which to perform first you must work from left to right. This is the standard law.

Reply 538

Original post by Jonty99

BIDMAS, then working from left to right gives 288 as the answer.

:s-smilie:

To get 2 as the answer, you need to assume things about the position of the 2 which we cannot be sure of from the form the equation is written in.

I totally agree!

Reply 539

CameraGirl