Year 12 2012 Chit Chat Thread (3 Viewers)

[JINOUGA]

Re: The Thread that never Ends

ok i'm all over this like brown on rice
i'm having a brain fart though

how many 6 digit numbers can be written using the numbers 1, 1, 2, 5, 8, 9? is it 6! or 5! the repeated 1 is throwing me off and i'm retarded so you know

you take the number of digits, in this case 6, so you have 6! ways of rearranging 6 digits

however note that the 1 is repeated, so you place 6! over the number of repeats factorial, in this case this will be 2! as 1 is repeated 2 times

therefore as khorne and shadowdude stated earlier, its 6!/2!

 

[kfnmpah]

Re: The Thread that never Ends

but why does that work? I never would have guessed dividing by the (number of repeated numbers)!

 

[kfnmpah]

Re: The Thread that never Ends

and so, for example, 114459 there would be 6!/4! = 30 combinations?

this is making lyf so much easier

 

[RealiseNothing]

Re: The Thread that never Ends

and so, for example, 114459 there would be 6!/4! = 30 combinations?

this is making lyf so much easier

Nope.

 

[cheezcake]

Re: The Thread that never Ends

You have 6 digits you can choose from for the first digit, 5 for the second digit, 4 for the third digit and so on, so with 6 numbers you have 6x5x4x3x2x1 possibilities. But two of the numbers are the exact same so they can be switched around in all the possible combinations and it will be the same number which means half of the combinations are identical to half of the other combinations. So you have 6x5x4x3x2x1 divided by 2 combinations

or 6!/2!

 

[Shadowdude]

Re: The Thread that never Ends

and so, for example, 114459 there would be 6!/4! = 30 combinations?

this is making lyf so much easier

6/2!2!

because you have 2 repeats


Anyways, the best way I've found to do this question is through a reverse Hasse diagram of divisibility sort of thing

So you go:

2: 720 - 360 - 180 - 90 - 45
3: 720 - 240 - 80
4: 720 - 180 - 45
5: 720 - 144
6: 720 - 120 - 20
8: 720 - 90
9: 720 - 80

And then you make similar divisiblity trees for the numbers at the end... and you add up cases and... yeah. still working through this method though

 

[JINOUGA]

Re: The Thread that never Ends


A nice explanation of the concept imo

 

[cheezcake]

Re: The Thread that never Ends

What the hell is a reverse Hasse Diagram

 

[Sy123]

What is your atar aim?

 

[Shadowdude]

Re: The Thread that never Ends

What the hell is a reverse Hasse Diagram

You'll learn it if you do graph theory.

Basically allows you to partially order things. In this case, a partial order through divisibility.

 

[Arcorn]

Re: The Thread that never Ends

View attachment 26294
A nice explanation of the concept imo

What textbook is that from?

 

[JINOUGA]

Re: The Thread that never Ends

What textbook is that from?

it is from a book called The Mathematical Toolchest by the Australian Mathematics Trust

a nifty little book that has some really neat explanations for a few topics

 

[Shadowdude]

Re: The Thread that never Ends

Okay so assuming AAEldar's solution is right - the possible combinations are:

Two 1s

865311 - can be arranged 6!/2! = 360 ways
664511 - can be arranged in 6!/2!2! = 180 ways
445911 - can be arranged in 6!/2!2! = 180 ways
985211 - can be arranged in 6!/2! = 360 ways

One 1
338521 - can be arranged 6!/2! = 360 ways
942521 - can be arranged 6!/2! = 360 ways
334541 - can be arranged 6!/2!2! = 180 ways
654321 - can be arranged 6! = 720 ways
662521 - can be arranged 6!/2!2! = 180 ways

No 1s
334252 - can be arranged 6!/2!2! = 180 ways
922252 - can be arranged 6!/4! = 30 ways
522236 - can be arranged 6!/3! = 120 ways

Total: 3210 ways


there you go nicola

 

[Arcadian Empire]

Re: The Thread that never Ends

Okay so assuming AAEldar's solution is right - the possible combinations are:

Two 1s

865311 - can be arranged 6!/2! = 360 ways
664511 - can be arranged in 6!/2!2! = 180 ways
445911 - can be arranged in 6!/2!2! = 180 ways
985211 - can be arranged in 6!/2! = 360 ways

One 1
338521 - can be arranged 6!/2! = 360 ways
942521 - can be arranged 6!/2! = 360 ways
334541 - can be arranged 6!/2!2! = 180 ways
654321 - can be arranged 6! = 720 ways
662521 - can be arranged 6!/2!2! = 180 ways

No 1s
334252 - can be arranged 6!/2!2! = 180 ways
922252 - can be arranged 6!/4! = 30 ways
522236 - can be arranged 6!/3! = 120 ways

Total: 3210 ways


there you go nicola

no ways to arrange no 1s....= total number of ways to arrange - total number of ways to arrange any number with 1?

ur p. shit for a maths major

 

[Shadowdude]

Re: The Thread that never Ends

no ways to arrange no 1s....= total number of ways to arrange - total number of ways to arrange any number with 1?

ur p. shit for a maths major

what's the total number of ways to arrange then


pls work through that and i think you'll find it won't work

 

[Fawun]

You're assuming that your essay fits perfectly to the question- in the test it'll probs take longer than 30 minutes (maybe a few mins depending on how good you are at adapting to questions). Two questions- do you have reading time and is everything weighted equally (like is essay the same mark value as creative)?

Respond to this in chit chat = ) (lol- I'm becoming Carrot)

I'm pretty sure that the question will be something like "How are ideas or issues represented through your close study of text" or something like that. If not, then i'm pretty screwed because I memorised all 800 words of my essay lol. Yes we have 10 minutes reading time. What do I do during that 10 minutes reading time? and yes everything is weighted equally I think. If not, what do I do? LOL

 

[deswa1]

I'm pretty sure that the question will be something like "How are ideas or issues represented through your close study of text" or something like that. If not, then i'm pretty screwed because I memorised all 800 words of my essay lol. Yes we have 10 minutes reading time. What do I do during that 10 minutes reading time? and yes everything is weighted equally I think. If not, what do I do? LOL

Ok. Here's what you do. Reading time starts- look at essay and creative questions and mentally plan them both out. You said creative is your weakest- HERE work out what you are going to do. Then begin reading the comprehension texts and the questions so you know how to answer them. Now how to proceed from here depends on the individual test- general exam theory says do short answer first because you just read the texts so you don't need to re-read them. You can knock this off fairly quickly (~35 mins)- make sure to write decent amounts for your stuff. Then you want to do the essay so knock that off. If you think you'll forget stuff, jot down a very short plan right after writing time starts. Then do creative.

All three sections are worth equal amounts- it doesn't make sense to split time 30-30-60 imo. If creative is your weakest, spend longer by all means but not double the time. Remember you have reading time to sort out a lot of stuff.

And that english question would be the easiest in the world- if you don't get that, remember to answer the question they give you. You can use the same quotes and techniques and stuff, just change your intro and your linking between quotes (on a simplistic level)

 

[Fawun]

Ok. Here's what you do. Reading time starts- look at essay and creative questions and mentally plan them both out. You said creative is your weakest- HERE work out what you are going to do. Then begin reading the comprehension texts and the questions so you know how to answer them.

I only have 10 minutes of reading time, how am I suppose to do all that in 10 minutes? :s

Now how to proceed from here depends on the individual test- general exam theory says do short answer first because you just read the texts so you don't need to re-read them. You can knock this off fairly quickly (~35 mins)- make sure to write decent amounts for your stuff. Then you want to do the essay so knock that off. If you think you'll forget stuff, jot down a very short plan right after writing time starts. Then do creative.

Where do I jot it if they don't give me like spare paper? I use a pen and I can't jot it down on my exam paper because then I will need to write my essay on it. So should i just do essay first, then creative and then comprehension since that's probably the easiest?

All three sections are worth equal amounts- it doesn't make sense to split time 30-30-60 imo. If creative is your weakest, spend longer by all means but not double the time. Remember you have reading time to sort out a lot of stuff.

If I spend longer, that means that I have to cut some of the times of my other sections right? hence why 30-30-60. 60 for creative because that's my weakest and that it'll probably take me 20 minutes to come up with a plan.

 

[Shadowdude]

Ten minutes is plenty of time. It'll take you like two minutes to read through the questions anyway.

 

[deswa1]

So tomorrow, for English Extension, I haven't found 1 of the 2 related texts required of us. We have to do a 1 hr essay + 1 hr creative - thinking of playing chicken with my friends. Y/N?

Y. Make up a related- not to hard. Bonus points if you give it a funny author like Wayne Rooney or something (people did that last year). An even better one- for the EX1 creative, people played what we called the Oedipus game. Basically, your total points is calculated by multiplying your mark out of 25 by the amount of times you write Oedipus in your creative. I think one guy hit over 100 but there were like 15 creatives where the main character was Oedipus- I want to know what the markers thought when they read it

when u get dux what u gunna say?

Yeah What now!!! Nah I won't get dux lol- there's one guy that's beating me in every sub (except phys where we tied ) so he'll get it probs. But hey, if I end up with dux, I'll think of something sexy to say

What about you?