• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

Harder test this year? (1 Viewer)

lolrofllol

Member
Joined
Feb 29, 2008
Messages
127
Gender
Male
HSC
2009
Did you even check to see if your equation worked? I got your answer originally however after plugging in values for x and realising it was WAY out i was able to work out how to solve it. Extrapolate line, measure amount. Then do gradient which i took from y= 7 down to y = -1.2, divide this by 65 which is from 0 to 65 on the extrapolation. Gradient = 0.1261. Y intersects at -1.2. Therefore y = 0.1261x - 1.2. Checked that equation and i was able to do y = 0.1261x(65) - 1.2. This gives 7. Looking at the graph 65 cm corresponds to 7 kg. Maybe im wrong but thats how i'm seeing it, can anyone else clarify this?. Also if u use y=0.232x(65)+1.2 = 16.28 kg. This cant be as 65 clearly corresponds to 7 kg.
Dude it's not the actual height but the CHANGE in height from 40, you know? So 0.232 * 25 (65 - 40 = 25) + 1.2 = 7 <br><br>
EDIT: you probably wont get very accurate answers with other values because it's only correlation? i'm not sure. I did my answer and i'm not sure if it's right, it's just the way i did it.
 
Last edited:

Macdwg

Professional Mad Lad
Joined
Jun 15, 2008
Messages
93
Gender
Male
HSC
2009
Maybe you're right. Hmmm. Question says "The height and mass of a child are measured and recorded over its first two years" perhaps its all in that that suggests the idea of 'change'... Its just that it says 'the mass AND height'.
Fuck.
 

lolrofllol

Member
Joined
Feb 29, 2008
Messages
127
Gender
Male
HSC
2009
Maybe you're right. Hmmm. Question says "The height and mass of a child are measured and recorded over its first two years" perhaps its all in that that suggests the idea of 'change'... Its just that it says 'the mass AND height'.
Fuck.
I looked at it logically, there is a negative y intercept if you extrapolate because they don't really measure the child until its born. So when the child is born, it assumes the shortest child is 40cm, hence 40cm is the logical 0 value for x.
 

Sau

New Member
Joined
Apr 3, 2009
Messages
13
Gender
Female
HSC
2009
this year the paper had more money questions and i dont like those question
but i would it was half good and hlaf bad
 

Question?

New Member
Joined
Jan 29, 2007
Messages
24
Gender
Undisclosed
HSC
2008
I got y = 0.232x + 1.2, I thought it was wrong too, but i realised the height of a child did not start at zero and hence x = the growth rate, not the acutal height. Incredibly hard exam, others pale in comparison. Same probability for 27c?
yeah i got the same thing. i just took two points from the LINE not the points from the table and got the same thing.. is it right??
 
Last edited:

Book Freak

Whovian
Joined
Aug 3, 2007
Messages
43
Location
Cronulla
Gender
Female
HSC
2009
I was so confused when I did the multiple choice, I was going "C, C, C, C, B, C... THIS CAN'T BE RIGHT!!!" still, from what i heard a lot of ppl had the same answers, so maybe it was! One girl in my year ran out of time and guessed the entire multiple choice, nice one
 

oxyray

goodluck.
Joined
Nov 26, 2008
Messages
21
Location
Campbelltown
Gender
Female
HSC
2009
im not that great at maths im coming 10th in my year but i found that paper pretty easy compared to others years. maybe it was my 3am cram sesh, but it payed off. however, what that F is theoretical probability hahaa. i just .... i reallly dont know what i did but i tried hitting a stone for marks basically.
 

oxyray

goodluck.
Joined
Nov 26, 2008
Messages
21
Location
Campbelltown
Gender
Female
HSC
2009
I was so confused when I did the multiple choice, I was going "C, C, C, C, B, C... THIS CAN'T BE RIGHT!!!" still, from what i heard a lot of ppl had the same answers, so maybe it was! One girl in my year ran out of time and guessed the entire multiple choice, nice one
i had the same secquence cccc b or very very similar! and lolll one of my friends guessed the entire mc aswell. i had plenty of time!!! unlike the goddam trials.
 

jordzy

New Member
Joined
Sep 15, 2008
Messages
10
Gender
Female
HSC
2009
dont quote me incase im wrong but im looking at about +98 in the test and as for the graph question. you are right the line COULD have been extrapolated but it crossed the Y intercept at 1.1 it was a negative X intercept which ment nothing in terms of the equation of the line.

my final answer was - Y = 0.115x + 1.1 - i plugged a few values in and it seemed to work out.

also the test was by far easier than many other years in my opinon.
 

f1r3c4p3

Member
Joined
Mar 9, 2009
Messages
30
Gender
Male
HSC
2009
For multiple Choice I got

C C C A D A A D C B B C B D D A C B B B D A

My mum said that she thinks I got 20/22 :s
 

stormstealer27

Tashii the mentalrunaway
Joined
Nov 1, 2007
Messages
39
Location
Sydneyyy
Gender
Female
HSC
2009
hmm it did throw me off knowin me i made heaps of STUPID mistakes!

*sighs*

Maths was never my strong point ahhaa XD


hope i did gud XD
 

sadcase

New Member
Joined
Aug 26, 2009
Messages
12
Gender
Male
HSC
2009
For 28 b i) i got a strong positive linear and for
ii)y=0.24x+1.2
please sorrect me if i am wrong
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top