Free General Mathematics resources · VCE Units 3 & 4
A full VCAA-style practice paper with a marking guide, plus original practice questions and a study planner — sent straight to your inbox.
A data set of monthly rainfall (mm) has a mean of 48 and a standard deviation of 6. Assuming an approximately normal distribution, between what two values do about 95% of the months lie?
1 mark for applying the 95% rule (mean plus or minus 2 standard deviations): 48 - 2(6) and 48 + 2(6). 1 mark for the correct interval: between 36 mm and 60 mm.
The number of hours studied (x) and the test score (y) for a group of students gives a least-squares line y = 12 + 4.5x. Interpret the slope of this line in context.
1 mark for identifying the slope as 4.5. 1 mark for a correct contextual interpretation: for each additional hour studied, the test score is predicted to increase, on average, by 4.5 marks. 'On average / predicted' is required for the mark.
More to practise: all General Mathematics practice questions.