helloo there!

In this year's new study design, three median regression line// do you mean three point median smoothing? if so, then it is included (part of core)!
However, hire purchase is no longer involved. -> (I know this because, while doing (2015 ver.) checkpoints recently, there was a question related to hire purchase, which left me completely confused)
Core this year is different from previous study designs. It is split into two;
data analysis (part 1) which consists of: univariate x bivariate data, frequency tables x bar charts, box plots x five number summaries, standard deviation x mean media mode, scatterplots, coefficient of determination, residual analysis, data transformations etc.
and
financial and recurrence relations (part 2; similar to business maths but with an addition of recurrence relations) which consists of:
recurrence relations, depreciation, compound interest investments x loans, reducing balance loans, annuities (+ investments) x perpetuity etc.
And in regards to calculating GST, I'm not too sure myself! If anything tho, it isn't involved in the core for sure.
Hope this was helpful!
