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Esse

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I don't know but it seems to just be a misinterpretation of the wording/requirement of the question (although the first part of the Q. should've made it clear what the interpretation is). So you should at least get some marks (guessing). Maybe lose 1? You could ask Carrotsticks for his opinion.
Thank you :)
 

mrstripedshades

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Looking at some answers, I counted the mistakes I knew I made, and I think I'll get a raw in the 80s. Could be mid, but depends on the way they mark in terms of correct solution because I made some very silly errors near last step of calculation for a couple questions.

Would be happy with a flat 80 even tho, so not that bummed out. Even tho I still COMPLETELY fed up the multi choice idk I was so panicked lmao
 

Nexa579

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What's your definition of n and p()? In the Q., we're saying the game ended at or before roll#(n-1). So if n = 10, you'd need to have gone up to roll #9.
n is the same n in the question ie the nth roll.
p(...) is p(game ending before the nth roll is more than 3/4)

Seems like the consensus is that n is not 10 tho.

No it's not. You did something wrong in your working, when n=12 then p> 3/4
From memory,
When n = 10, probability = 0.74...
When n = 11, probability = 0.76...
When n = 12, probability = 0.77.. or 0.78..?
 

WrittenLoveLetters

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Yeah, I'm hovering in the 80s. Definitely not the high 80s IMO.

Fuck it, going to pray for a pretty solid Band 5 in Maths.
 

Esse

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Anyone have predictions on what that will align to? 2014 - 86 raw was a 90, and that exam was much easier than this :)
 

trecex1

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n is the same n in the question ie the nth roll.
p(...) is p(game ending before the nth roll is more than 3/4)

Seems like the consensus is that n is not 10 tho.



From memory,
When n = 10, probability = 0.74...
When n = 11, probability = 0.76...
When n = 12, probability = 0.77.. or 0.78..?
Checked this many times during and after exam, you should get something like P= 1-(7/8)^2{n-1}
n=11 yields ~0.74
n=12 yields ~0.77
Maybe you summed your GP wrong.
 

Speed6

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Im on 88 sparingly zzzzzzzzzzzz
Lmao, I went onto the site which you linked me and guess what.. I never knew Leehuan was well-known on there? Since when did he do the switch?

Also, for the range question, on that site Integrand, the OP put the range as 0<y<200. Is this a mistake? That's what I also had in the exam. Why is it 10<y<200? And also, will I loose all marks for that question?
 

Esse

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Lmao, I went onto the site which you linked me and guess what.. I never knew Leehuan was well-known on there? Since when did he do the switch?

Also, for the range question, on that site Integrand, the OP put the range as 0<y<200. Is this a mistake? That's what I also had in the exam. Why is it 10<y<200? And also, will I loose all marks for that question?
Sub t = 0, you get 10 xD, and you should only lose 1 as you found the other side
 

pikachu975

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What method did you use (sorry if you said this above already, I haven't followed this thread too closely)? If you did the parabola method I mentioned before, it's self-evident really. Plus the question's wording makes it sounds like they let you assume it (if I recall the question correctly).

Looking back at the Q. now, it's two marks. So at least you should have some working out, and the answer. It'd probably be best to justify when the maximum occurs (e.g. concave down parabola). If you use this parabola method, you don't need to test, just need to do something like mention it's a concave down parabola, so it's maxed at the vertex etc.
I did let R = the growth rate

R = y/400 (200 - y)
R = y/2 - y^2 / 400

dR/dy = 1/2 - y/200
SPs when dR/dy = 0
1/2 - y/200 = 0
100 - y = 0
y = 100 yabbies

and just left it there. I'm pretty sure I'm going to lose one for testing maybe...
 

trecex1

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Almost certain I got 99/100 with one mark lost on MC Q10...

Apparently I can't do basic log laws ffs
 

InteGrand

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I did let R = the growth rate

R = y/400 (200 - y)
R = y/2 - y^2 / 400

dR/dy = 1/2 - y/200
SPs when dR/dy = 0
1/2 - y/200 = 0
100 - y = 0
y = 100 yabbies

and just left it there. I'm pretty sure I'm going to lose one for testing maybe...
Your R is still the parabola. Did you mention the concave down parabola part?
 

pikachu975

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Almost certain I got 99/100 with one mark lost on MC Q10...

Apparently I can't do basic log laws ffs
I reckon 99 raw will be a state rank for sure.

Also to Integrand above:

Nah I didn't mention concave down, that was all my working. Got lazy and didn't bother testing now I get punished for it lol. Also was worried I didn't have enough time to solve the square finding the height of a building question and the 1 + x + x^2 .... question but finished those in the end.
 

Shuuya

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I reckon 99 raw will be a state rank for sure.

Also to Integrand above:

Nah I didn't mention concave down, that was all my working. Got lazy and didn't bother testing now I get punished for it lol. Also was worried I didn't have enough time to solve the square finding the height of a building question and the 1 + x + x^2 .... question but finished those in the end.
I got it through trial and error and have literally no working, so don't worry :p
 

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