ATAR Notes: Forum

Archived Discussion => 2010 => End-of-year exams => Exam Discussion => Victoria => Further Mathematics => Topic started by: _avO on November 03, 2010, 05:59:00 pm

Title: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 05:59:00 pm
Havn't been through the other threads but these are suggested solutions for the 3 modules and core (credits goes to jasoN-)

Core:
1a) 50%
b) med=28
ran=56
IQR=17
c)1/6 (16% for canada)
d) approximately symmetric
2a) male income
b) $350
c) $18250
ci) extrapolation
3a) plot
b) increasing trend (as years increases, GDP increases)
c) GDP = 20000 + 524 x time
d) 34148, error of $752

Graphs:
1a) R = 65x
b) C = $1700
c) sketch
d) 20 pillows
2) 40
3a) the total number of pillows sold must not exceed 150
b) k = 45
ci) sketch
ii) sketch
d) $9075
e) let Snorestop = 2x, x + y + 2x less than or equal to 150
  =>  3x + y less than or equal to 150
f) R = 175x + 50y
g) (35,45), R = $8375

Networks
1a) 0 means can't directly communicate
b) f = 1, g = 0
2a) 11 mins
b) Hamilton path
ii)(attached)
3a) D
bi) B, D, F
ii) 32
c) B and D
4a) 2 activities
b) 9 minutes
c) A, C
d) 4 min
e) 16 min
f) ABDH

Matrices
1a) N = [4 8 2]
b) P = [26]
c) Oscar scores 26 points
2a) 20% heavy this week to moderate the next week
b) 66
c) 6
3a) [1 1 1]
     [2 -1 3]
     [1 2 1]
b) x = -5
c) 10 rebounds
4ai) A2 = [2100]
             [1100]
ii) 3200 caps
b) A10 = [2163]
             [1613]
c) gradually more people attend until eventually 3000 people attend, with no change in the future
d) Less people attend over time until eventually 600 people attend with no change in the future

Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 06:06:05 pm
Hmm for Q1, wouldn't it be 1/2 not 50%, since it asked for a proportion? The rest is all correct pretty sure.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:07:35 pm
Proportion can be fraction of percentage (even decimal), no specification
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: xoxogossipgirl on November 03, 2010, 06:14:53 pm
this makes me feel better - I thought I screwed up matrices and didn't have enough time to check but I'm pretty sure I still got them right
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:19:51 pm
Do you guys think we had to write GDP (dollars) = 20000 + 524 x time (years)

sigh.. I think I wrote dollars but not years
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: nbalakers24 on November 03, 2010, 06:23:27 pm
Hmm for Q1, wouldn't it be 1/2 not 50%, since it asked for a proportion? The rest is all correct pretty sure.

this was tested in the past both fractions and percentage was accepted also decimals i.e. .50
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Benny1234 on November 03, 2010, 06:27:11 pm
No you definitely did not have to right GDP(dollars) and time (years) as the question asked for the equation in terms of GDP and time..... however if you did write dollars after GDP I think that will be accepted
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: johsephhh_ on November 03, 2010, 06:31:10 pm
NICE i put 1/2
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Studyinghard on November 03, 2010, 06:32:13 pm
did you have to mention the steady state for the matrices. In that it stops at 600 or whatever
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:33:31 pm
Well the steady state means that it won't change in the future, so as long as you say one or the other it should be correct
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Shem on November 03, 2010, 06:48:32 pm
GODDAMMIT!

I put B D and C for the cycling networks question, and the total as 33km. Are you 100% confident on yours?  :-[
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jezza2010 on November 03, 2010, 06:49:54 pm
Do you guys think we had to write GDP (dollars) = 20000 + 524 x time (years)

sigh.. I think I wrote dollars but not years

nah it said take time as the independent variable so writing GDP=20000 + 524 * time would have been fine. dont think you would be marked wrong if you wrote dollars and time
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:50:25 pm
I tried that one and it came out as 33

The points were B, D and F
Yeah i tried like 2 different methods and they both came out as 32km
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jezza2010 on November 03, 2010, 06:50:34 pm
GODDAMMIT!

I put B D and C for the cycling networks question, and the total as 33km. Are you 100% confident on yours?  :-[

defs it is 32 went over both paths 4-5 times defs added to 32!
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 06:54:24 pm
Why is it 3200 caps?
What did the question ask again?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:55:17 pm
asked how many free caps were expected to be given. it was the sum of elements in matrix A2 which was 2100+1100
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 06:57:00 pm
But didn't it say for people who attended the first and second game?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Blakhitman on November 03, 2010, 06:58:44 pm
pretty sure it said the scorpions in week 3 and dinosaurs in week 2.

So you added Scorpions from A3 to dinosaurs from A2
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 06:59:31 pm
Are you freaken serious? didn't even notice that they were different.. er..
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 06:59:58 pm
Ok must have read it wrong. How many marks was that question worth?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 07:00:07 pm
Nope it was the total amount from people attending the second game of D and S pretty sure.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Studyinghard on November 03, 2010, 07:00:16 pm
No im pretty sure this was 3200
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: Studyinghard on November 03, 2010, 07:00:33 pm
fck scared the crap out of me. STOP DOING THAT :P
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:00:53 pm
lol im sorry.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:01:34 pm
Yep U PULLED OUR LEGS
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:05:27 pm
was that worth one mark?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:06:12 pm
Yeah it is
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:07:04 pm
I lose marks on the easiest questions :(
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:09:05 pm
I lost one on extrapolation thought too logically I wrote "Realistically, a female's annual income is not explained by a male's income.. "etc.. LOL

Btw do you lose marks if you get it right, but then go on to write other stuff. For example the one about (matrices) Oscar getting 26 points, I wrote he got it by getting 4 one-pointer 8 two-pointer and 2 three-pointers..
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 07:10:40 pm
Yeah you should get the mark for matrices, my teacher told me they can't mark you down for writing too much
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:10:51 pm
Should be fine as long as you wrote he scored a total of 26 points in that game.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:12:43 pm
You know for the linear part, the very last question would i get at least a mark for listing the possible coordinates but not the  max profit?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:13:30 pm
I think so, if you identified the coordinates that were altered as a result in different constraints, that is worth 1 mark (otherwise simply putting the correct revenue got the 2 marks)
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: vidang on November 03, 2010, 07:15:23 pm
guys how did you do matrices 2d?
how'd you prove it

i just said s7 = T^6 x [90 150 60]
and said that 90 + 150 + 60 = 50 + 150 + 100
hence 300 = 300
is that okay?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:19:48 pm
You needed to find S7 and S8(Or Sn when n>7) as it shows there is no change in the future therefore it is the steady state
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 07:20:25 pm
I showed what T^7 was then what T^8 was. Couldn't it have been  raaised to the power of anything greater than or equal to 6?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: vidang on November 03, 2010, 07:22:06 pm
FUCK
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 07:22:49 pm
Anything that shows that the future doesn't change so you can do T^100 and then explain that both T^7 and T^100 are the same hence no change
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: vidang on November 03, 2010, 07:26:17 pm
i lost
core: 1 mark
linear: 1 mark
networks: 2 marks
matrcies: 3 marks- 2 marks becaause i typed it into my calculator wrong instead of 150 i typed 50 FUCK ME MAN :(
could've gotten 40 :'(
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: onerealsmartass on November 03, 2010, 07:31:32 pm
i lost
core: 1 mark
linear: 1 mark
networks: 2 marks
matrcies: 3 marks- 2 marks becaause i typed it into my calculator wrong instead of 150 i typed 50 FUCK ME MAN :(
could've gotten 40 :'(
devo right?? i did a similar thing with the last question in matrices :'(
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: menashiiii on November 03, 2010, 07:54:33 pm
I tried that one and it came out as 33

The points were B, D and F
Yeah i tried like 2 different methods and they both came out as 32km

so if ive said b c d f for bi
will i get consequential mark for ii?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: physics on November 03, 2010, 08:18:19 pm
so i did the G * a1 and then i get a2 and then i do G*a2 and i get a3 but then i did this to the a10 and my answers always had a 1000 difference between each other??????? how did u guys get that answer?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 08:19:20 pm
do G^9 A1 is the same as doing all that (I double checked :))
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 08:20:25 pm
hahah I did the long way because I was scared that something dodgy was gonna happen :P
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: physics on November 03, 2010, 08:22:02 pm
do G^9 A1 is the same as doing all that (I double checked :))
i did do it the long way and they suggested we do it that way didnt they? and i got that answer
i think u should do it again cause i got a diff answer.wtf. :(((((((((((((((((
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: clarksta123 on November 03, 2010, 08:53:49 pm
Awks for me... lol
core Q1d I said because there are no outliers, would i get the mark you reckon?
also networks q3bii I got 31...
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 09:38:11 pm
I think you had to describe the shape as well, because despite there being no outliers, the shape could have been skewed therefore the mean does not measure the centre
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 09:39:49 pm
Awks for me... lol
core Q1d I said because there are no outliers, would i get the mark you reckon?
also networks q3bii I got 31...

How'd you get 31?
I got 33 at first then realised there was a 32.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: emmmm on November 03, 2010, 09:44:16 pm
i got 31 also
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 09:55:20 pm
wow..31? i did like at least 5-6 different combinations and couldn't get below 32..
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 09:57:06 pm
Omg so the answers 31???
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: vidang on November 03, 2010, 10:01:32 pm
WTF networks 31?
omg fml
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 10:02:21 pm
No, it's 32
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 10:03:16 pm
Are you sure?
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 10:05:59 pm
Pretty sure
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: jasonn93 on November 03, 2010, 10:06:36 pm
Phew :)
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: vidang on November 03, 2010, 10:07:34 pm
someone have the netowkrs exam section
someone prove that its 31 :\
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 10:08:02 pm
That question was so annoying, took me like 10 minutes.
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: _avO on November 03, 2010, 10:08:20 pm
3+4+2+3+2+2+3+4+3+6 = 32

other possibility

6+4+3+4+2+2+3+3+2+3 = 32
Title: Re: Suggested solutions for Core, Graphs, Networks and Matrices (Exam 2!)
Post by: LFTM on November 03, 2010, 10:09:34 pm
3+4+2+3+2+2+3+4+3+6 = 32

other possibility

6+4+3+4+2+2+3+3+2+3 = 32

Yeah i got 2 possibilities also when trying to work this out.