Methods Exam 1

[knightrider]

I have heard the spesh people at my school say they had an advantage for the last question?

What did they mean by this?(just curious)

[wunderkind52]

I have heard the spesh people at my school say they had an advantage for the last question?

What did they mean by this?(just curious)

I assume they meant in terms of finding the coordinates, since its sort of sinilar to resolving forces

[GeniDoi]

I have heard the spesh people at my school say they had an advantage for the last question?

What did they mean by this?(just curious)

I guess for finding T if you approached it using vectors you can reach T by going
OT = OC + CT = 2i + 0j + 2cos(theta)i+2sin(theta)j  = (2 + 2cos(theta))i + 2sin(theta))j

And a similar thing for the second question.

Knowing vector operations will definitely have given you a conceptual edge in this sort of question.

[Splash-Tackle-Flail]

I had a look again, and actually to be technically correct the answer for 10b) should be either -cos(ɵ)/sin(ɵ) or -cot(ɵ). The gradient of the tangent to the circle is actually defined at ɵ = pi/2. If your answer is -1/tan(ɵ) it will be undefined at ɵ = pi/2 but if you take ɵ=pi/2 on the graph it is clearly defined (the gradient will be zero).

I had a look again, and actually to be technically correct the answer for 10b) should be either -cos(ɵ)/sin(ɵ) or -cot(ɵ). The gradient of the tangent to the circle is actually defined at ɵ = pi/2. If your answer is -1/tan(ɵ) it will be undefined at ɵ = pi/2 but if you take ɵ=pi/2 on the graph it is clearly defined (the gradient will be zero).

But surely they wouldn't take a mark off for that? Like are they that brutal??

Also just realised I misinterpreted the last part of Q9. But then I read this on the Facebook page:

 "bii is a question of interpretation. Usually part ii of a question is separate to any information obtained from part i.
If this is the case, then part ii tells us that Pr(B)=0.3; therefore p=0.7.
If not, then part ii tells us that Pr(B|W)=0.3; therefore p=7/16.
Hopefully people complain to vcaa and both solutions are marked correct!"

then a response:

"no it isn't, not only is this part ii of part b, meaning the two answers should be linked, but even if it wasn't linked, the answer would be 7/16. This is because it says the probability that THIS egg came from part B, and THIS egg is white, meaning the appropriate given that formula would need to be used and give you 7/16 anyway."

then:

" b) "another egg is selected at random from the set of all eggs at the warehouse" (no suggestion that this random egg must be white)

ii. Probability that THIS^ egg is from farm B=0.3"

"Oh yeah you're right, if anything now I am more convinced that the answer is 0.7.  I think that's the way I interpreted it the first time actually, I definitely see where you're coming from and I think they might have to award a mark to everyone"

 Would anyone be able to clarify this?

[Zealous]

Thanks for uploading the exam! (I just had a go at it)

That was definitely one of the harder exam 1's. It really felt like VCAA were being stingy with a lot of their mark allocations and as a result it was more time consuming than most Exam 1's I reckon; no real diabolical question though (not that there's usually any on exam 1).

Yeah. I agree. Everything is worth like 1-2 marks... what happened to the 3-4 mark questions from a few years back? Question 9 and 10 looked pretty annoying also.

All the best for tomorrow's exam!

Would anyone be able to clarify this?

Personally I would've found the probability given the egg has a white eggshell, since I would read the question in sequence, from (b) to (bi), then to (bii). I wouldn't jump back to "Another egg is selected at random" before attempting (bii).

Also, it does say in (bii) "If the probability that THIS egg came from farm B is 0.3", which seems to point to it being same egg from (bi). Just what I would do though.

I had a look again, and actually to be technically correct the answer for 10b) should be either -cos(ɵ)/sin(ɵ) or -cot(ɵ). The gradient of the tangent to the circle is actually defined at ɵ = pi/2. If your answer is -1/tan(ɵ) it will be undefined at ɵ = pi/2 but if you take ɵ=pi/2 on the graph it is clearly defined (the gradient will be zero).

I would've just done -tan(pi/2-theta). Looks messy though O.o

[Splash-Tackle-Flail]

Personally I would've found the probability given the egg has a white eggshell, since I would read the question in sequence, from (b) to (bi), then to (bii). I wouldn't jump back to "Another egg is selected at random" before attempting (bii).

Also, it does say in (bii) "If the probability that THIS egg came from farm B is 0.3", which seems to point to it being same egg from (bi). Just what I would do though.

oh damn I guess I over-complicated things then. I was literally overanalysing every word of that question.

Given it's ambiguity, do you think there will be any leeway from VCAA?

[Zealous]

Given it's ambiguity, do you think there will be any leeway from VCAA?

The telephone question (Q4) from VCAA 2012 Exam 1 was pretty ambiguous, but VCAA only allowed one interpretation to get the marks. So, it looks like it may be one way or the other.

[4lec]

hopefully we get a repeat of 2011 where 34 was an a+

otherwise rip in peace methods

Was the exam super hard or was the cohort uhh...lack luster?

[Splash-Tackle-Flail]

The telephone question (Q4) from VCAA 2012 Exam 1 was pretty ambiguous, but VCAA only allowed one interpretation to get the marks. So, it looks like it may be one way or the other.

Yeah in that case, the 7/16 answer does make more sense. Did they justify only allowing one interpretation for the 2012 exam 1?? I think I just need to break the question down, instead of acting super suspicious towards each question looking for wording tricks. (thing that got me was I did the whole working for 7/16 then when checking over it again, I crossed it out and went for p=0.7; aw well, nothing I can do 'bout it now

[Mershian]

Thought it was a pretty fair exam. With so many little questions it was easy to drop marks IMO, so while it seemed "easy", I thought it was fair.

Think I got around 31-33 which will probably be a B+/A?

Am I still capable of getting a 35 raw?

And finally congrats to everyone who completed the exam today and good luck for tomorrow! 

[Orb]

Thought it was a pretty fair exam. With so many little questions it was easy to drop marks IMO, so while it seemed "easy", I thought it was fair.

Think I got around 31-33 which will probably be a B+/A?

Am I still capable of getting a 35 raw?

And finally congrats to everyone who completed the exam today and good luck for tomorrow! 

There have been people getting 40+ with less than 31 on E1, so you're fine

[Splash-Tackle-Flail]

Just a quick question, is it true that methods is as competitive as further on the top end? Like one mark lost is one study score lost?

And is there a way to tell what the scaling for methods would be this year?

[Orb]

Just a quick question, is it true that methods is as competitive as further on the top end? Like one mark lost is one study score lost?

And is there a way to tell what the scaling for methods would be this year?

Yes. Pretty much. It could be as bad as half a mark lost = 1 study score.
i.e Last year 1.5 marks lost = 50, 2 marks lost = 49, 2.5 marks lost = 48, assuming full SACs.

Iirc in 2006, losing 3 marks netted you a 45.

I'd envisage that this year will turn out similar to 2014, depending on tomorrow ofc. However, once you move past 45, it becomes more like 2-3 marks per S.S

[keltingmeith]

Just a quick question, is it true that methods is as competitive as further on the top end? Like one mark lost is one study score lost?

And is there a way to tell what the scaling for methods would be this year?

Tbh, this true for the upper end of pretty much every subject. Remember that you're graded to a bell curve, the difference between a 49 and a 50 is literally 0.1%, and similar for a 48 and 49.

I had a look again, and actually to be technically correct the answer for 10b) should be either -cos(ɵ)/sin(ɵ) or -cot(ɵ). The gradient of the tangent to the circle is actually defined at ɵ = pi/2. If your answer is -1/tan(ɵ) it will be undefined at ɵ = pi/2 but if you take ɵ=pi/2 on the graph it is clearly defined (the gradient will be zero).

You raise a very good point, actually. However, this is a MASSIVE subtlety, and I can't see them refusing to award it, because you would not know this unless you did specialist or chose not to use 1/tan(t). If they do choose to be exclusive like that, methods teachers will put them in so much strife that this question will NEVER appear again.

I'm very interested to see the examiners report for this question, now - because it actually looks like theta=pi/2 would give the /true/ maximum.

[knightrider]

There have been people getting 40+ with less than 31 on E1, so you're fine

In regards to this.

Say if you got a B+ to A for exam 1.

and then for exam 2 you get a really high A+ then is it still possible to get a 40+ score.
Also assuming you got a B+ to A for exam 1.
What would you need on exam 2 to get a 40 + score
Thanks