Post Ext 1 Papers/Marks/Ranks (1 Viewer)

[kpq_sniper017]

I want to compare my half-yearly Ext 1 paper with some other people's. So, if you could, could you post your paper, your marks (if possible) and your rank (if possible).
I don't have a scanner at home, but I can type out some of the questions from my half-yearly. I got 80% in my half-yearly for 3U and I ranked 3rd in total and 1st in my class (Yr11 accel. - 9 people) - about 30 in total (inc. Yr12 3U and Yr12 4U)

 

[nike33]

post the last qn of the paper / or hardest so i can see the difficulty?

 

[~*HSC 4 life*~]

i got 77% for my Ext 1 and i'm not really that happy with it grrrr

last q was a parametric Q...i may type it up later

 

[George W. Bush]

Last question: Find an expression in terms of n for S(n) if
S(n) = 6 + 66 + 666 + .... with the last term being n sixes.

 

[Heinz]

Originally posted by George W. Bush
Last question: Find an expression in terms of n for S(n) if
S(n) = 6 + 66 + 666 + .... with the last term being n sixes.

How many marks was this one worth? 3?

 

[Xayma]

Hmm would that be
S_n=
6(10^n-1+2x10^n-2+3x10^n-3+4x10^n-4+.....+(n-1)x10¹+nx10⁰)

 

[kpq_sniper017]

Question 4: (last question)

a) Three numbers whose product is 216 are in geometric progression. If 1, 4, 8 are subtracted from them respectively the results are in arithmetic progression. Find the numbers (6 marks)

b) A_n and B_n are two series given by:

A_n = 1² + 5² + 9² + 13² + ....... + (4n-3)²
B_n = 3² + 7² + 11² + 15² + ....... for n = 1, 2, 3......

(i) Find the n^th term of B_n. (1 mark)

(ii) If S_2n = A_n - B_n prove that If S_2n = -8n² (3 marks)

(iii) Hence, or otherwise, evaluate
101² - 103² + 105² - 107² + ...... + 2001² - 2003² (2 marks)


I got part a) of Q4. I was the only one in my class to get it, but 2 4U students also got it.
I also got part b) (i), but I couldn't get the rest. I ran out of time.
IMO, a) was pretty easy, but the last 2 parts of b) were fairly tough. Although the teacher said it was actually a fairly easy question. Time was the biggest factor in my exam. We had 60 minutes to complete it. (4 Qs - 12, 13, 13, 12 = 50 marks)

I got 80% for the exam: 12, 13, 8 and 7 respectively. Other two got 44 and 46 I think (not in my class so I don't know). If you haven't read my other post, these two guys got 49/50 for 3U last year, but want to come first in the state so they're doing it again. (apparently).

 

[kpq_sniper017]

Originally posted by ~*HSC 4 life*~
i got 77% for my Ext 1 and i'm not really that happy with it grrrr

last q was a parametric Q...i may type it up later

parametrics in an hsc yr 12 exam??
just on that.....can examiners randomly throw in preliminary work in an hsc exam btw. i'm not talking about the hsc exam or trials coz i know they can in those. i'm talking about half-yearly's and term assessments.

 

[CM_Tutor]

Pcx_demolition017, question 4(b) is a (very slightly modified) steal from a past trial paper. The version I have seen asks for the series:

101² - 103² + 105² - ... + 1993² - 1995²

so it was almost certainly a 1995 trial, and I think it might have been SGS, but I'm not sure.

I mention this because if your school will steal questions for the half-yearlies, then it's well worth practicing from those sources before the trials.

Originally posted by Xayma
Hmm would that be
S_n=
6(10^n-1+2x10^n-2+3x10^n-3+4x10^n-4+.....+(n-1)x10¹+nx10⁰)

I'm sure there is a nicer expression than this one - the question is far too easy if the answer is left as this.

Originally posted by pcx_demolition017
parametrics in an hsc yr 12 exam??
just on that.....can examiners randomly throw in preliminary work in an hsc exam btw. i'm not talking about the hsc exam or trials coz i know they can in those. i'm talking about half-yearly's and term assessments.

They can examine whatever they tell you they are going to examine.

 

[George W. Bush]

CMTutor is right, there is a far nicer expression than that. And yes, 3 marks, i believe.

It was a while ago.

 

[Xayma]

Originally posted by CM_Tutor
I'm sure there is a nicer expression than this one - the question is far too easy if the answer is left as this.

Yeah I know but thats all I could think of without writting it down on paper to establish a pattern.

My paper was mainly bits of old HSC papers so it is no use posting.

 

[Heinz]

Originally posted by George W. Bush
Last question: Find an expression in terms of n for S(n) if
S(n) = 6 + 66 + 666 + .... with the last term being n sixes.

T₁ = 6
T₂ = 66
T₃ = 666

S₁ = 6
S₂ = 72 = 6 (11 + 1)
S₃ = 738 = 6(11² +2)
S_n = 6(11^n-1 +n - 1)

My 3u paper was pretty straight forward, 3D trig question 7

 

[CM_Tutor]

Originally posted by Heinz
T₁ = 6
T₂ = 66
T₃ = 666

S₁ = 6
S₂ = 72 = 6 (11 + 1)
S₃ = 738 = 6(11² +2)
S_n = 6(11^n-1 +n - 1)

This isn't the answer, as:

S₄ = 6 + 66 + 666 + 6666 = 7404

but your answer gives S₄ = 6(11^4-1 + 4 - 1) = 6(1331 + 3) = 8004

 

[Heinz]

Originally posted by CM_Tutor
This isn't the answer, as:

S₄ = 6 + 66 + 666 + 6666 = 7404

but your answer gives S₄ = 6(11^4-1 + 4 - 1) = 6(1331 + 3) = 8004

Rats, shouldve gone to S4 to test it out. Back to the drawing board..

 

[George W. Bush]

Try using Sigma.

 

[redslert]

everyone has differnet paper at different difficulty, you shouldn't compare with other's

 

[Estel]

pcx's question was very similar to a JR trial

 

[George W. Bush]

If anyone cares about my 6 + 66 etc. question

S(n) = 2/3 (9 + 99 + 999 + 9999 ...)
= 2/3 (10 + 100 + 1000 + 10000 ..... - n) (or use sigma with 10^n - 1)
= 2/3 (10(10^n-1)/9 - n )

 

[kpq_sniper017]

Originally posted by Estel
pcx's question was very similar to a JR trial

lol....my friend also said that his tutor said that it was similar to a past exam question. do teachers often do that??? coz that's cool

back to my question.......would u consider it easy/average/moderate/difficult/out of 10 maybe (10 being the hardest)? the exam we had:
- had four questions totalling 50 marks
- we had 60 minutes.

some other guy said that we should have been given 90 mins for the sort of exam i was given taking into account the difficulty of the last question. any opinions would be appreciated.

 

[Estel]

If that was 1/4 of the test you gave us, then no I don't think it's very difficult.

Ninety minutes for four of those?... shades of my common test
5 stupidly straightforward questions in 2 hours... Might as well have been a 40 minute topic test... It seems that they don't want our average to be 50% again this time.