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March 28, 2024, 10:03:16 pm

Author Topic: Standard Math Q+A Thread  (Read 181119 times)  Share 

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RuiAce

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Re: General Math Q+A Thread
« Reply #255 on: May 15, 2017, 08:22:58 pm »
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{Jokers are conventionally excluded in Poker.}[/tex]







Ahh thankyou so much! So essentially its: 52 x 51 x 50 x 49 x 48 over 5 factorial? Then with the 4 favourable outcomes over 2 598 960, which simplifies to the answer, 1/649 740?

Yep;

natasha.rh

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Re: General Math Q+A Thread
« Reply #256 on: May 24, 2017, 02:18:16 pm »
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hi,
does anyone have any past papers on the focus study: health and mathematics?
much appreciated!

jamonwindeyer

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Re: General Math Q+A Thread
« Reply #257 on: May 24, 2017, 02:52:25 pm »
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hi,
does anyone have any past papers on the focus study: health and mathematics?
much appreciated!

Hey! It might be worth having a bit of a look in this collection - There's heaps there, I'm not sure if any of it will be for this Focus Study but worth a shot! ;D

natasha.rh

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Re: General Math Q+A Thread
« Reply #258 on: May 24, 2017, 03:38:54 pm »
+1
Hey! It might be worth having a bit of a look in this collection - There's heaps there, I'm not sure if any of it will be for this Focus Study but worth a shot! ;D
so many papers! thank you so much!!!

Lachlan Morley

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Re: General Math Q+A Thread
« Reply #259 on: May 29, 2017, 05:55:25 pm »
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Hi all,
This question is in regard to un ordered and ordered selections

When a question states how many possible selections are able to occur, is it unordered or order, I always thought that unordered in the question needed to state " How many diffrent possible selections" as that is what takes the double ups out

RuiAce

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Re: General Math Q+A Thread
« Reply #260 on: May 29, 2017, 06:02:56 pm »
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Hi all,
This question is in regard to un ordered and ordered selections

When a question states how many possible selections are able to occur, is it unordered or order, I always thought that unordered in the question needed to state " How many diffrent possible selections" as that is what takes the double ups out
Sometimes it can be inferred from the question whether you should treat it as ordered are unordered. The wording of the question may imply that common sense should be used.

But that being said I didn't do general either. Could I please see the question(s) involved that lead to this query?

Lachlan Morley

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Re: General Math Q+A Thread
« Reply #261 on: May 30, 2017, 12:20:19 pm »
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Sometimes it can be inferred from the question whether you should treat it as ordered are unordered. The wording of the question may imply that common sense should be used.

But that being said I didn't do general either. Could I please see the question(s) involved that lead to this query?

The question was of 15 Basketball players, 4 were selected for the team . How many possible ways can these individual be selected

I was always taught that how many possible ways meant that you include all the double ups as whilst they are including the same players , they express it in a different way so there fore is a different way of doing it therefore not dividing by factorial. If the question said how many different possible ways it would obviously mean to divide by the factorial although the question docent ask the different ways it asks how many possible ways so I'm under the assumption that I don't divide by the factorial as that wouldn't be answering the question

RuiAce

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Re: General Math Q+A Thread
« Reply #262 on: May 30, 2017, 12:28:36 pm »
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I don't necessarily agree with that convention. That's pretty restricting on what makes intuitive sense.

For this particular problem, the way I see it is that if persons A B C and D made the team, then this would be equivalent to saying persons D C B and A made it. There isn't a ranking or hierarchy system here or something, there's just one single team with four members. This implies that repetition of cases does exist, and that I do need to divide by the factorial here.

If, for example, I had to choose positions specifically (e.g. center, forward), then I would not divide by 4!.

The important thing to realise is that division by the factorial is for an unordered selection, which is what we have here. If we have an ordered selection, then we should definitely not divide.
« Last Edit: May 30, 2017, 12:32:19 pm by RuiAce »

amorphous

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Re: General Math Q+A Thread
« Reply #263 on: June 06, 2017, 11:45:15 am »
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Hi guys! I have math question I'm stuck on, can someone please help me? Thank you.

It takes one man one day to dig a 4m x 4m x 4m hole. How long does it take 4 men working at the same rate to dig 16m x 16m x 16m hole?

jamonwindeyer

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Re: General Math Q+A Thread
« Reply #264 on: June 06, 2017, 12:04:34 pm »
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Hi guys! I have math question I'm stuck on, can someone please help me? Thank you.

It takes one man one day to dig a 4m x 4m x 4m hole. How long does it take 4 men working at the same rate to dig 16m x 16m x 16m hole?

Hey! So one man can dig out a volume of 4x4x4=64 cubic metres per day. 4 men, therefore, can dig out quadruple that - 64x4=256 cubic metres, per day.

Now, the hole we are digging is 16x16x16=4096 cubic metres. To get our answer, we just go 4096/256=16 days! Does that make sense?

MisterNeo

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Re: General Math Q+A Thread
« Reply #265 on: June 06, 2017, 12:08:49 pm »
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Hi guys! I have math question I'm stuck on, can someone please help me? Thank you.

It takes one man one day to dig a 4m x 4m x 4m hole. How long does it take 4 men working at the same rate to dig 16m x 16m x 16m hole?

Hi! The answer is 16 days.


Divide 4096 by 256.
Hence, 16 days!
« Last Edit: June 11, 2017, 09:37:11 pm by MisterNeo »

Kirri Rule

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Re: General Math Q+A Thread
« Reply #266 on: June 06, 2017, 07:55:30 pm »
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Hi sorry we have a maths exam coming up next week on only 4 specific topics and was wondering if anyone knew where to find papers or questions that are releated to specific topics.( As I have already done all the past HSC and textbook questions.) Thank you

RuiAce

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Re: General Math Q+A Thread
« Reply #267 on: June 06, 2017, 08:01:19 pm »
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Hi sorry we have a maths exam coming up next week on only 4 specific topics and was wondering if anyone knew where to find papers or questions that are releated to specific topics.( As I have already done all the past HSC and textbook questions.) Thank you
It is honestly not a bad idea to pluck out only the relevant past papers out of trials and just do them

The website may have some other useful things though.

Kirri Rule

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Re: General Math Q+A Thread
« Reply #268 on: June 06, 2017, 08:05:30 pm »
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It is honestly not a bad idea to pluck out only the relevant past papers out of trials and just do them

The website may have some other useful things though.
I know sometimes in the HSC and Trial questions there are like the questions that have hidden underlying topics like the capture recapture questions, how should we look at the question to see what topic its from? Thanks

RuiAce

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Re: General Math Q+A Thread
« Reply #269 on: June 06, 2017, 08:10:59 pm »
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The line might be blurrier for general maths comparatively speaking with the other courses but you should have a solid idea of which topics are from where. Some will speak out to you which topic they're from because they only require one thing.

If you can guarantee that you reach a point where you know it won't be in the exam, go ahead and just look at the answers to confirm your instinct.

Essentially, if a question looks as though it involves concepts in the topics you're being examined on you should never disregard it. You can only jump when you're positive it's safe to. I personally don't advise it (because why should you when you can prepare for the trials a bit as well) but if you're in time pressure with studying that's what I'd say.