CSSA trial (advanced/ extension maths) (1 Viewer)

[tywebb]

There were no professors. Only 1 of them is a uni lecturer and he was not even the convenor. The other 4 are from high schools.

It s not impossible. Here are my solutions: https://4unitmaths.com/cssa2023adv-tywebb.pdf

CSSA's answer to their 2023 Adv paper Q28b is wrong. They should have checked ln(16/9)-1 is negative and so the distance is ln(9/16)+1 (or written as ln(9/16) - -1 as question said to write it as ln(a/b)-c)

 

[carrotsss]

CSSA's answer to their 2023 Adv paper Q28b is wrong. They should have checked ln(16/9)-1 is negative and so the distance is ln(9/16)+1 (or written as ln(9/16) - -1 as question said to write it as ln(a/b)-c)

Checking doesn't seem to be CSSA's strong point because in the CSSA solutions for their 2023 Ext.2 paper Q16c there are actually 2 answers 219.1m/s OR 223.5m/s. They arise from the equation
View attachment 39610
In CSSA's solution the absolute value blissfully disappears and then they only get 1 answer 219.1m/s.

I was not so careless and put my solutions here for comparison and you will see how I got the 2 solutions: https://4unitmaths.com/cssa2023e2-tywebb.pdf

cssa seem to have a tendency of giving dodgy solutions, they have lots of problems in chemistry and physics as well

 

[tywebb]

cssa seem to have a tendency of giving dodgy solutions, they have lots of problems in chemistry and physics as well

If the markers are made aware of this before they mark it then it won't matter.

But are they?

If not then dodgy solutions = dodgy marks.

Even worse - if some are made aware of it and others aren't, not only are the marks dodgy, but unfair as well, eg., some students getting marks and other students losing marks - for the same answer!

 

[tywebb]

I also put up my solutions to the Ext. 2 CSSA 2023 at https://4unitmaths.com/cssa2023e2-tywebb.pdf

I used an out-of syllabus method for question 12aii choosing 3 planes out of 6 to find the point of intersection of the 2 lines using a matrix equation. This turned it into a question about the intersection of 3 planes having the same point of intersection as the 2 lines.

 

[tywebb]

Also my solutions to the Ext. 1 CSSA 2023 are at https://4unitmaths.com/cssa2023e1-tywebb.pdf

Note in 14a for the extension 1 I used the regularised incomplete beta function, which although outside the syllabus, gets the answer much quicker.

Furthermore use of the complementary error function instead of the table gives a more accurate answer.

 

[Luukas]

It is not impossible. Here are my solutions ...

May I ask why you put expenses as 200 + 20n in Q23? Doesn't that make the expenses in the first week 220? The question says that they start at 200 and then increase by 20 per week.

 

[Luukas]

If you were taught properly you would not feel so bad about it.

This comment is very similar to what I hear the teacher who led the writing team has been saying to his class - and that he feels sorry for students who have teachers complaining that the exam was too difficult...

 

[SadCeliac]

Anyone know what the averages and top marks were for the CSSA math advanced 2023 trial in different schools

bump I have a friend who's asking (or was this answered already lol)

 

[its_ace21]

bump I have a friend who's asking (or was this answered already lol)

my school the average was in the high 60's and ppl got in the 80's and maybe 90's

 

[SadCeliac]

alr ill tell him 60s lol

 

[its_ace21]

alr ill tell him 60s lol

in other schools averages were fails i think

 

[breadcrumbs]

bump I have a friend who's asking (or was this answered already lol)

my schools avg was like 30 or 40 something and only one person got above 80