Updated November 2026. These KCSE 2026 Mathematics Paper 1 (121/1) predicted questions are built from past-paper trends: we ranked the topics that past KCSE Mathematics Paper 1 papers test most often, then wrote original practice questions on them. They are not leaked, official or guaranteed questions, and this site is not linked to KNEC or KICD. Use them to practise the areas most likely to appear, alongside your full syllabus revision.
KCSE Mathematics 121/1 prediction: most commonly tested topics
The ranking below comes from the topic coverage of past KCSE papers, as summarised in our paper guides. It is a ranking, not an exact count: exam papers change every year.
| Rank | Topic | How it is usually tested |
|---|---|---|
| 1 | Algebra (expansion, factorisation, simplifying fractions) | Section I short items |
| 2 | Quadratic equations | Solve by factorising or formula, often inside a word problem |
| 3 | Indices and logarithms | Evaluate without tables, solve index equations |
| 4 | Commercial arithmetic | Currency exchange, commission, hire purchase |
| 5 | Simultaneous equations | Word problems on prices or ages |
| 6 | Trigonometry and circles | Sine/cosine rule, arc length, sector area |
| 7 | Mensuration | Surface area and volume of solids and frustums |
| 8 | Linear graphs and inequalities | Gradient, equation of a line, shading regions |
| 9 | Rates, ratio and proportion | Sharing, mixtures, work rates |
| 10 | Transformations | Reflection, rotation, enlargement on a grid |
Free sample: 3 KCSE 2026 Mathematics Paper 1 predicted questions
Q1. Solve for x: 32x+1 = 243.
Marking scheme
243 = 35, so 2x + 1 = 5 and x = 2.
Q2. Factorise fully and simplify: (x2 − 9) / (x2 + x − 6).
Marking scheme
(x−3)(x+3) / ((x+3)(x−2)) = (x − 3)/(x − 2), for x ≠ −3, 2.
Q3. A trader buys a radio for KSh 4,000 and marks it 30% above cost. She then gives a 10% discount. Find her percentage profit.
Marking scheme
Marked price = 5,200. Selling price = 0.9 × 5,200 = 4,680. Profit = 680, so 680/4,000 × 100 = 17%.
Full set: 17 more predicted questions with marking scheme
17 more predicted questions with full marking schemes are locked. They cover every topic in the table above.
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Frequently asked questions
Are these the real KCSE 2026 Mathematics Paper 1 questions?
No. Nobody outside KNEC knows the real questions, and any site claiming a leak is lying or breaking the law. These are original practice questions written by the CBC Guide team, predicted from the topics past KCSE papers test most often.
Which topics come up most in KCSE Mathematics Paper 1 (121/1)?
The most commonly tested areas in past papers are Algebra (expansion, factorisation, simplifying fractions), Quadratic equations, Indices and logarithms, Commercial arithmetic. The full ranked list is in the table above.
How do I get the full set of predicted questions?
The first 3 questions are free. The remaining 17, each with a marking scheme, unlock with the KSh 20 Day Pass or the KSh 500 Monthly Pass, paid by M-Pesa. The passes do not auto-renew.
How should I use predicted questions in the last days before the exam?
Answer each question under time, mark it with the scheme, then go back to your notes for any topic you got wrong. Do not skip topics that are not on this list, because KNEC can test any part of the syllabus.
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