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2026 QCE General Mathematics exam: What to learn from last year's mistakes
Hi all, in preparation for the upcoming exam, here's what to learn from last year's mistakes.
2025 exam median and average: not stated in QCAA's report.
The exam was 95 raw marks and worth 50% of the subject result. Paper 1 had 57 marks; Paper 2 had 38.
I've gone through the report and marking guide. These are four questions I'd redo before another full paper.
QCAA doesn't publish written-question averages. These are marking traps, not claims about how many students made each error. This covers the General paper.
Paper 1, Q17b: Comparing travel times
3 marks.
Where an answer loses marks: Comparing the number of students without allowing for different group sizes.
What you needed: 11 of 17 Year 6 students travelled for less than 15 minutes, compared with 3 of 12 Year 10 students. That's 64.7% versus 25.0%, a gap of about 39.7 percentage points. Use that comparison to support an association between year level and travel time. The table doesn't prove year level causes the difference.
Paper 1, Q19: Seasonal indices
4 marks across parts a and b.
Where an answer loses marks: Dividing by the wrong year's average, or averaging the sales figures instead of the seasonal ratios.
What you needed: The quarterly average was 32,500 for 2023 and 31,375 for 2024. For quarter 3, calculate 94,000/32,500 and 82,000/31,375, then average those two ratios. The seasonal index is about 2.75. Keep the unrounded values until the final step.
Paper 1, Q20: Loan repayments
4 marks.
Where an answer loses marks: Treating the whole repayment as a reduction in the loan balance.
What you needed: Start at A₀ = 24,000 and use Aₙ₊₁ = 1.0045Aₙ − 557. The first two balances are $23,551 and $23,099.98. The principal fell by $900.02 over those two payments, not $1,114. Interest accounts for the difference.
Paper 1, Q22b: Effective annual interest
2 marks.
Where students needed more care: The report specifically flags effective annual rates. A nominal rate isn't automatically the effective rate.
What you needed: With 4.94% nominal interest compounded fortnightly, calculate (1 + 0.0494/26)^26 − 1. The result is about 0.05059, or 5.06% a year. Dividing 4.94% by 26 only gives the periodic rate; it doesn't finish the question.
For 2026, critical-path work uses activity-on-arc networks. The Hungarian algorithm includes minimisation and maximisation problems up to 5 × 5. Check the current formula book alongside old papers.
Use the 2025 report alongside official marking guide. 2026 syllabus changes.
Figures and criteria: QCAA. Explanations paraphrased from its materials, © State of Queensland (QCAA) 2025–2026, CC BY 4.0.
Use the General Mathematics hub and past papers and marking guides alongside this.
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