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December 06, 2020, 10:04:36 am

### AuthorTopic: Sample solutions to QCAA's sample papers  (Read 788 times)

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#### RuiAce

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##### Sample solutions to QCAA's sample papers
« on: August 25, 2019, 09:13:58 pm »
+9

To get a better feel for how your exams will be administered, I will release solutions to the sample papers QCAA have recently released. For Maths Methods, the papers can be accessed here.

Note that these solutions serve only as samples and are not endorsed by any other party.

Click on each image to zoom into an appropriate width

I actually feel very critical about a select few elements in the papers. Some of my thoughts are given in the sections.

Paper 1

Questions 1-10 (Multiple Choice)
This section was pretty good.

Questions 11-20 (Multiple Choice)
This is perhaps more of a personal thing that I have on Q12. I'm not too sure why we're allowed to just use the seasonality indices for the 2005-2017 data and be done with it. There should be a reason why we don't need to incorporate the seasonality indices from 2018 in, but I haven't been able to figure out what.

Questions 21-25
This section was pretty good.

Questions 26-30
Question 26 b) confused me a lot, because it's completely unclear as to how they expect this to be done. It is worth 1 mark, so naturally the use of technology would be expected. But I haven't found any evidence pointing in that statistics modes on calculators must be explicitly taught to students.

This could potentially also disadvantage students who aren't well equipped with the calculator. Some students might stare at their formula sheet wondering how they plan to write something so long on the paper, in a matter of 2 lines.

Question 30 gives so little marks for finding the critical path. Though forwards/backwards scanning can be done pretty quickly for this graph, there should be more merit available.

Also, the LST for activity G should technically come before the critical path is found. I have no idea why the order here is switched.

Paper 2

Questions 1-5
Question 2a) - drawing the complete graph on 5 vertices with weights on the edges is extremely messy work for just 1 mark.

Questions 6-9
Question 6 is unclear. There really is no rule stating whether midnight is meant to correspond to the start or the end of the day. In fact, with conventions, it's more common for midnight to be assumed as the start of the day. So to obtain the required answer (this is based off a real life event), it would make more sense to say it happened at midnight on 30 December 2011.

Question 8 is unclear in what they want in my opinion. In reality, $R^2$ values should be here. But the syllabus has already said that students are not expected to compute it; only use it.

The next bet is then the correlation coefficient, but again this is a lot of work for just 3 marks. Plugging into what's given on the formula sheet takes HEAPS of effort. On the other hand, if it was intended that a calculator be used, what is the purpose of having the formula on the sheet?

Between Q7 and Q8 - why does the 7 mark question have more writing space than the 3 mark question?

Question 9 gives way too little marks for the forecasting. The seasonal adjustments required in the process and the fact that multiple least squares lines must be fit is at least as tedious as something like Question 7 with the table of values work. (Also similar to other methods of solving Q7.)

#### Joseph41

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##### Re: Sample solutions to QCAA's sample papers
« Reply #1 on: August 26, 2019, 09:06:22 am »
+1

#### XD12345

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##### Re: Sample solutions to QCAA's sample papers
« Reply #2 on: October 27, 2020, 03:47:06 pm »
0

To get a better feel for how your exams will be administered, I will release solutions to the sample papers QCAA have recently released. For Maths Methods, the papers can be accessed here.

Thank you so much for these answers, it helped me a lot with setting out my questions!

I totally agree with what you said about question 9 by the way, that question would take up a considerable amount of time and requires a lot of calculations to only be worth 4 marks.

Note that these solutions serve only as samples and are not endorsed by any other party.

Click on each image to zoom into an appropriate width

I actually feel very critical about a select few elements in the papers. Some of my thoughts are given in the sections.

Paper 1

Questions 1-10 (Multiple Choice)
This section was pretty good.

Questions 11-20 (Multiple Choice)
This is perhaps more of a personal thing that I have on Q12. I'm not too sure why we're allowed to just use the seasonality indices for the 2005-2017 data and be done with it. There should be a reason why we don't need to incorporate the seasonality indices from 2018 in, but I haven't been able to figure out what.

Questions 21-25
This section was pretty good.

Questions 26-30
Question 26 b) confused me a lot, because it's completely unclear as to how they expect this to be done. It is worth 1 mark, so naturally the use of technology would be expected. But I haven't found any evidence pointing in that statistics modes on calculators must be explicitly taught to students.

This could potentially also disadvantage students who aren't well equipped with the calculator. Some students might stare at their formula sheet wondering how they plan to write something so long on the paper, in a matter of 2 lines.

Question 30 gives so little marks for finding the critical path. Though forwards/backwards scanning can be done pretty quickly for this graph, there should be more merit available.

Also, the LST for activity G should technically come before the critical path is found. I have no idea why the order here is switched.

Paper 2

Questions 1-5
Question 2a) - drawing the complete graph on 5 vertices with weights on the edges is extremely messy work for just 1 mark.

Questions 6-9
Question 6 is unclear. There really is no rule stating whether midnight is meant to correspond to the start or the end of the day. In fact, with conventions, it's more common for midnight to be assumed as the start of the day. So to obtain the required answer (this is based off a real life event), it would make more sense to say it happened at midnight on 30 December 2011.

Question 8 is unclear in what they want in my opinion. In reality, $R^2$ values should be here. But the syllabus has already said that students are not expected to compute it; only use it.

The next bet is then the correlation coefficient, but again this is a lot of work for just 3 marks. Plugging into what's given on the formula sheet takes HEAPS of effort. On the other hand, if it was intended that a calculator be used, what is the purpose of having the formula on the sheet?

Between Q7 and Q8 - why does the 7 mark question have more writing space than the 3 mark question?

Question 9 gives way too little marks for the forecasting. The seasonal adjustments required in the process and the fact that multiple least squares lines must be fit is at least as tedious as something like Question 7 with the table of values work. (Also similar to other methods of solving Q7.)