Standard Math Q+A Thread

[emilyygeorgexx]

Hey, is there a way to calculate the interquartile range without writing/ordering every single number on paper? Like, say there were 200 numbers, is there a proper formula for this?

Hey!

If you didn't want to calculate the IQR by hand, you can just pop the numbers on the calculator (if you have the scientific one) and it will calculate the IQR for you!

[Razeen25]

Now that the website is back online...Yes. Keep in mind that maths is different to every other subject in that the preliminary course is EXAMINABLE. Up to 20% of the final exams are allowed to include content taught in the preliminary course.

Anything goes in maths. All of it is in play.

I NEVER KNEW THIS. I dropped to general at the start of year 12, and I guess now I’m just realising the immense workload I must catch up with - that is, all the prelim content I never learnt. Why math gotta do peeps who drop down like this smh 

[Potatohater]

I NEVER KNEW THIS. I dropped to general at the start of year 12, and I guess now I’m just realising the immense workload I must catch up with - that is, all the prelim content I never learnt. Why math gotta do peeps who drop down like this smh 

It'll be ok, I did the same, and since the HSC content is mostly an extension of the prelim content you won't have to work too hard to catch up if you've got a solid understanding of the HSC content, which, from mathematics 2U I guess you do. A lot of it's pretty easy, the only things I remember having to distinctly go over because I didn't already know them from yr10 and below, is the yr11 case studies and some of the financial stuff, but other than that going over the whole course isn't super nessecary

[joemassoud]

Hey Guys,

If anyone could please explain this question and what exactly is a linear function is and how to identify one

Thanks in advance!

[RuiAce]

Hey Guys,

If anyone could please explain this question and what exactly is a linear function is and how to identify one

Thanks in advance!

The linear function must take the form \(y=mx+b\), meaning only y’s and x’s appear. The only plausible option is B, which is \(y=-x+12\) rearranged.

A fails because of the \(\frac1x\), whih makes it a hyperbola
C fails because of the \(x^2\), which makes it a quadratic (parabola)
D fails because of the \(2^x\), which makes it an exponential

[joemassoud]

Hey Guys,

I have my half yearly coming up next week and the topics being assessed are:

1. Loans and Annuities
2. Equations and Linear Functions
3. Further Applications of Area and Volume
4. Statistical Distributions

I have completed all my school's past papers and topic tests given by my teacher. If anyone can send me or let me know of any past paper resources or topic tests on the topics above that would be awesome!

Thanks!

[Potatohater]

Hey Guys,

I have my half yearly coming up next week and the topics being assessed are:

1. Loans and Annuities
2. Equations and Linear Functions
3. Further Applications of Area and Volume
4. Statistical Distributions

I have completed all my school's past papers and topic tests given by my teacher. If anyone can send me or let me know of any past paper resources or topic tests on the topics above that would be awesome!

Thanks!

Have you tried the HSC papers yet? You coul either sift through them manually looking for those topics or find a book that groups them together such as the checkpoints book

[jamonwindeyer]

Hey Guys,

I have my half yearly coming up next week and the topics being assessed are:

1. Loans and Annuities
2. Equations and Linear Functions
3. Further Applications of Area and Volume
4. Statistical Distributions

I have completed all my school's past papers and topic tests given by my teacher. If anyone can send me or let me know of any past paper resources or topic tests on the topics above that would be awesome!

Thanks!

Only because you asked for a suggestion, the ATAR Notes Topic Tests would be worth a look! I personally think they are incredible, and everything is divided by topic to make things easy to study

[emilyygeorgexx]

I NEVER KNEW THIS. I dropped to general at the start of year 12, and I guess now I’m just realising the immense workload I must catch up with - that is, all the prelim content I never learnt. Why math gotta do peeps who drop down like this smh 

Omg I feel you on another level! I dropped from 2U in the last term of Year 11, which meant I had to sit the General Maths Yearly. I had to learn everything they had covered in the whole year, and it was hard at first because of all the work I had missed and some of the concepts I had never seen before so I was like wtf. But it does get easier after that, you'll be so sweet and there's no reason to stress.

I legit had my half yearly on Monday this week and I have no idea how but I finished with 55 minutes to spare. Don't worry I didn't just sit there, I went back over my paper and redid some questions where I found mistakes.

Fingers crossed I actually did well!!

[Lumenoria]

Hey, for this question, do I calculate the cumulative frequency based on the first 163 or the last one?

[RuiAce]

Hey, for this question, do I calculate the cumulative frequency based on the first 163 or the last one?

The last.

The cumulative frequency is intended to be a running total of all the frequencies, so every instance of 163 must count as well. Therefore 10 is correct.

[Razeen25]

Hey, for this question, do I calculate the cumulative frequency based on the first 163 or the last one?

I’m actually confused. How do you calculate the cumulative frequency from a stem and leaf plot?

[Lumenoria]

The last.

The cumulative frequency is intended to be a running total of all the frequencies, so every instance of 163 must count as well. Therefore 10 is correct.

Thankyou!!

[Lumenoria]

Okay, so this is the solution on the answers for a past trial paper I've been doing, but I swear to god it's wrong - or I'm just really stupid. Can someone please confirm? My answer is waaay off this, and I swear I haven't done anything wrong because I've gotten the same answer three times. I don't understand why they've minused the a and the b when the formula clearly states you're supposed to add them?

[emilyygeorgexx]

Okay, so this is the solution on the answers for a past trial paper I've been doing, but I swear to god it's wrong - or I'm just really stupid. Can someone please confirm? My answer is waaay off this, and I swear I haven't done anything wrong because I've gotten the same answer three times. I don't understand why they've minused the a and the b when the formula clearly states you're supposed to add them?

Hey!

You need to plus the upper base and lower base of the trapezium, not minus them!

That has to be the wrong answer!