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48÷2(9+3) = ?

timiop2008

mhm lets over complicate things lol

48÷2(9+3) = a ÷ b(c+d) = (a) ÷ (bc+bd) = (a) ÷ (b(c+d))

a = 48
b=2
c=9
d=3

our formula LOL (a) ÷ (b(c+d))

substitute in (48) ÷ (2(9+3)) = (48) ÷ (2(12)) = (48) ÷ (24) = 2

or you may do it like this (48) ÷ (2(9+3)) = (48) ÷ (18+6) = (48) ÷ (24) = 2

or like this... 48÷2(9+3) = 2

the key is not the distributive law thing its common sense either youve got that or you dont, if it was like 2+2 ÷ (9+3) then youd get 4 ÷ 12 cose nothings connected to the bracket, you always do the connected to the bracket bits first if this is like a troll thingy its a really good one lol.

oh and you do know when it says 48 ÷ 2(9+3) it means 48 over 2(9+3)

48 48
--------- = ------------ =2
2(9+3) 24

Well done. You are correct. The key is the distributive law. You have actually used it but possibly not realised. You have considering the problem as 48 over 2(9+3).
The distributive law says that you cannot not split up the 2(9+3). You have not and this is why you got the correct answer. Well done

Reply 561

Indian_Prince

15

Original post by timiop2008

Well done. You are correct. The key is the distributive law. You have actually used it but possibly not realised. You have considering the problem as 48 over 2(9+3).
The distributive law says that you cannot not split up the 2(9+3). You have not and this is why you got the correct answer. Well done

so you didnt like my formula :frown:

and i think the distributive law should be called the common sense law then lol thats like basic maths right there

Reply 562

Freerider101

12

Original post by youjustburnkid

BODMAS

BRACKETS 48÷2(12)
48÷24
Therefore the answer is 2.

But you have done the multiplication first, then the division

Reply 563

nuodai

17

Original post by timiop2008

Well done. You are correct. The key is the distributive law. You have actually used it but possibly not realised. You have considering the problem as 48 over 2(9+3).
The distributive law says that you cannot not split up the 2(9+3). You have not and this is why you got the correct answer. Well done

This has nothing to do with the distributive law. I could argue that we distribute multiplication by 48÷2 over the (9+3) bracket, in a similar way that you argued that only the 2 is distributed. There is no "law" which says that you have to distribute only what comes after the ÷ sign rather than the whole lot. It is ambiguous notation in that it's not clear whether the 9+3 is meant to be on the numerator or denominator of the fraction. This whole thing probably started because someone wrote this on some forum somewhere completely innocently when they meant one or the other of 2 or 288 and then someone misinterpreted it. Assuming this to be the case 42÷2(9+3) is equal to whatever the person who originally wrote it meant for it to mean. [Unless it was invented just for the sake of having a debate about order of operations, in which case the answer is simply that it's ambiguous.]

I mean, the intended value is more likely to be 2, but that doesn't mean that it is 2. The reason I say this is that if the 9+3 were meant to be on the numerator there are a multitude of other ways of writing it to make it at least a bit more obvious (even putting a * after the 2 would probably do). Also, if I were on here and saw someone write, say, 1+x/3+x I would assume it meant (1+x)/(3+x).

Also, this (because I can't be bothered typing it out again).

I wish people would stop with the whole "it's definitely {insert 2 or 288 here} and everything else is wrong; look at these rules I just made up to support my case".

(edited 13 years ago)

Reply 564

orionmoo

15

Original post by nuodai

This has nothing to do with the distributive law. I could argue that we distribute multiplication by 48÷2 over the (9+3) bracket, in a similar way that you argued that only the 2 is distributed. There is no "law" which says that you have to distribute only what comes after the ÷ sign rather than the whole lot. It is ambiguous notation in that it's not clear whether the 9+3 is meant to be on the numerator or denominator of the fraction. This whole thing probably started because someone wrote this on some forum somewhere completely innocently when they meant one or the other of 2 or 288 and then someone misinterpreted it. Assuming this to be the case 42÷2(9+3) is equal to whatever the person who originally wrote it meant for it to mean. [Unless it was invented just for the sake of having a debate about order of operations, in which case the answer is simply that it's ambiguous.]

Also, this (because I can't be bothered typing it out again).

I wish people would stop with the whole "it's definitely {insert 2 or 288 here} and everything else is wrong; look at these rules I just made up to support my case".

Quoted for truth :smile:

Reply 565

ada1023

Why was everyone on the first page getting 2?

48/2(9+3)

so with BODMAS
B - rackets
48/2(12)
There are no P - owers
D - ivide
24(12)
M - ultiply
288.
DONE.

I hope other people have come to the same conclusion, I didn't actually read past the first page of replies.

Reply 566

username533239

17

Original post by thegodofgod

However, you could also do:

(48 ÷ 2) x (9 + 3)

= 24 x 12

= 288

How on Earth did you get that? Stop making **** up

Reply 567

fwed1

11

I hope this comes up in the A level maths paper this year!

Reply 568

Indian_Prince

15

Original post by ada1023

Why was everyone on the first page getting 2?

48/2(9+3)

so with BODMAS
B - rackets
48/2(12)
There are no P - owers
D - ivide
24(12)
M - ultiply
288.
DONE.

I hope other people have come to the same conclusion, I didn't actually read past the first page of replies.

you were doing aight up till the 48/2(12) then i think you dont understand what that means it looks like this on paper :

48
-----------
2(12)

which then turns into

48
----------
24

which is 2 erm if u want to go into fractions simplify it lol which would get u

4
----------
2

which in a form that u may understand is the same as

4 ÷ 2 = 2

lol =/ :biggrin:

Reply 569

ma3arf

9

I can't believe this thread got this many replies.

Reply 570

orionmoo

15

Original post by nuodai

Indeed.

Up next: a poll on whether 18÷6÷3 equal to 1 or 9.

The one I like is 1 + 2 x 3. Plug it into MS Calculator Standard and you get 9, and into Scientific and you get 7!

Reply 571

thegodofgod

19

Original post by siwelmail

How on Earth did you get that? Stop making **** up

48÷2(9+3)

= 48 ÷ 2 x (9+3)

= 24 x 12

= 288

Using BIDMAS

Reply 572

CameraGirl

13

Original post by timiop2008

Yes, the answer is 2. But it is not clear. IMO Its masters or Ph.D level maths

i'm doing an undergraduate master with maths modules and i say it's 2 :wink:

hehe

whyyyyy is this neg repped, i'm clearly just messing around light-heartedly! some people on here get way too serious over jokes :P lulz

(edited 13 years ago)

Reply 573

delllboy

8

timiop2008

Yes, the answer is 2. But it is not clear. IMO Its masters or Ph.D level maths

timiop2008

My name is not Einstein and I never said that the problem was straight forward. In fact, in my last post I said I believed that the problem was masters or Ph.D level mathematics.

What you are missing is that you cannot state the number before the bracket as a fraction. This would split up the 2 and the (9+3) which is not allowed as clearly defined by the distributive law.

timiop2008

Well done. You are correct. The key is the distributive law. You have actually used it but possibly not realised. You have considering the problem as 48 over 2(9+3).
The distributive law says that you cannot not split up the 2(9+3). You have not and this is why you got the correct answer. Well done

nuodai

This has nothing to do with the distributive law. I could argue that we distribute multiplication by 48÷2 over the (9+3) bracket, in a similar way that you argued that only the 2 is distributed. There is no "law" which says that you have to distribute only what comes after the ÷ sign rather than the whole lot. It is ambiguous notation in that it's not clear whether the 9+3 is meant to be on the numerator or denominator of the fraction.

Lol at how this guy timiop2008 has argued the "distributive law" like 8 times to then be stomped on by nuodai. :ahee:

Reply 574

CameraGirl

13

Original post by Freerider101

But you have done the multiplication first, then the division

nope, done the brackets first. distributive law as stated. the 2 is part of the brackets. well that's how you should be looking at it anyway. bodmas is something to teach kids basic algebra and should not really be used because it's a bunch of bull.

Original post by fwed1

I hope this comes up in the A level maths paper this year!

i hope it comes up on my 2nd year uni maths paper! that would be epic.
would much prefer it than the revision at the moment i'm doing, on computing the solution to a multi-variable initial value differential equation using the method of characteristics. and fourier series. bleuuuuuuuuuuuuuuuuuuuuuuuuugh haha!

(edited 13 years ago)

Reply 575

timiop2008

1

Original post by nuodai

This has nothing to do with the distributive law. I could argue that we distribute multiplication by 48÷2 over the (9+3) bracket, in a similar way that you argued that only the 2 is distributed. There is no "law" which says that you have to distribute only what comes after the ÷ sign rather than the whole lot. It is ambiguous notation in that it's not clear whether the 9+3 is meant to be on the numerator or denominator of the fraction. This whole thing probably started because someone wrote this on some forum somewhere completely innocently when they meant one or the other of 2 or 288 and then someone misinterpreted it. Assuming this to be the case 42÷2(9+3) is equal to whatever the person who originally wrote it meant for it to mean. [Unless it was invented just for the sake of having a debate about order of operations, in which case the answer is simply that it's ambiguous.] I mean, the intended value is more likely to be 2, but that doesn't mean that it is 2.

Also, this (because I can't be bothered typing it out again).

I wish people would stop with the whole "it's definitely {insert 2 or 288 here} and everything else is wrong; look at these rules I just made up to support my case".

It is definitely 2 though. And how can you say the distributive law has nothing to do with this!?. Your argument that the distributive law is irrelavent is flawed. You say you can "argue that we distribute multiplication by 48÷2 over the (9+3) bracket". However, you cannot do this. The distributive law only applies to multiplications not divisions/(fractions). Therefore as soon as you split up any term from the 2(9+3) you have broken the distributive law of multiplication.

As well as not obeying the distributive law of multiplication, here is another reason that the answer is 2 and not 288:

Consider the working out for the answer 288:
48/2(9+3)
=(48/2) x (9+3)
=24 x (9+3)
=24 x 12
=288

The second step: (48/2) x (9+3) cannot be the correct working out because it implies that the original question was 48(9+3)/2 which clearly, it wasn't.

Reply 576

nuodai

17

Original post by orionmoo

The one I like is 1 + 2 x 3. Plug it into MS Calculator Standard and you get 9, and into Scientific and you get 7!

That's not quite as debatable (as it were) because that has a well-defined answer (7), and writing 1+2x3 is different to pushing [1] [+] [2] [×] [3] on a calculator, the latter of which, on MS Calc at least, is another way of finding (1+2)×3 (since the way it works is to move from left to right regardless of what operations you use). On the other hand, a string of minus or division signs does introduce ambiguity, depending on whether or not you buy the 'left to right' rule, which I certainly don't.

Reply 577

timiop2008

1

Original post by delllboy

Lol at how this guy timiop2008 has argued the "distributive law" like 8 times to then be stomped on by nuodai. :ahee:

You should have probably read my reply to him before you posted this. :smile:

Reply 578

delllboy

8

Original post by timiop2008

Consider the working out for the answer 288:
48/2(9+3)
=(48/2) x (9+3)
=24 x (9+3)
=24 x 12
=288

The second step: (48/2) x (9+3) cannot be the correct working out because it implies that the original question was 48(9+3)/2 which clearly, it wasn't.