GuidesMathsPaper 3 · last-minute revision
3 days to go

GCSE Maths Edexcel Paper 3: last-minute revision

Paper 3 is calculator, 1 hour 30 minutes, 80 marks, and it's your last chance to bring up any topic you dropped marks on across Papers 1 and 2. Here is where to focus.

Edexcel 1MA1
The plan

Your 3-day plan

One focus per day, building to a timed run. Work it in order.

3
3 days to go

The topics most likely to be the 'final sweep' questions on the last paper

  • Go back through your Paper 1 and Paper 2 mistakes (real ones, from mocks or past papers) and re-do those question types today
  • Practise 3 algebraic fractions questions: simplifying, then adding or subtracting over a common denominator
  • Work through 3 quadratic formula and completing the square questions, both methods for solving quadratics that do not factorise
2
2 days to go

Geometry and graphs that reward careful reading

  • Practise transformations and enlargement by a fractional or negative scale factor, both catch students out under time pressure
  • Do 3 questions on parallel and perpendicular line gradients: negative reciprocal is the one fact to have automatic
  • Revise angles in polygons, interior and exterior angle sums, including irregular polygons
1
1 day to go

Light review, not new content

  • Re-read your quadratic formula and completing the square steps one final time, get the order automatic
  • Skim through your weakest topic from the 3-day plan, do not start anything brand new tonight
  • Get an early night. This is your third and final paper, pace yourself to arrive calm, not cramming in the corridor
Priority order

The topics that come up most

Ranked from analysed past papers. Start at the top: if you run out of time, you will have covered the most-tested ground.

1

Algebraic Fractions

Higher tier only. A high-frequency multi-step topic: simplifying, then all four operations over a common denominator, often the largest single algebra question on the paper

2

Quadratic Formula

Very high frequency for solving quadratics that will not factorise. Edexcel gives you the formula, but you must substitute a, b, c correctly and simplify surds in the answer

3

Completing the Square

Higher tier only. Used to find the turning point of a quadratic graph without plotting it, and to solve quadratics in an alternative exact form

4

Transformations and Enlargement

A reliable geometry topic worth 3-5 marks. Fractional and negative scale factors are the Higher-tier trap: the shape shrinks or flips through the centre of enlargement

5

Angles in Polygons

A high-frequency topic across every series. Interior angle sum is (n-2) x 180 degrees, exterior angles always sum to 360 degrees, know both formulae cold

6

Parallel and Perpendicular Gradients

Higher tier only. Perpendicular lines have gradients that multiply to give -1 (the negative reciprocal), a fact examiners test directly and within longer graph questions

7

Growth and Decay

Compound growth and decay problems (population growth, depreciation) using the multiplier method, tested most series in a real-world context

8

Rearranging Formulae

A skill tested both on its own and buried inside longer problems. Practise rearranging formulae where the subject appears more than once

Your Knowledge Organisers

PrepWise has a one-page Knowledge Organiser for every topic above. In the final 3 days, use them the same way each time: cover the page, try to recall the method and a worked example from memory, check what you missed, then repeat the next day.

Open the Maths Knowledge Organisers
Cheat sheet

Exam technique

Rules specific to Paper 3. On this paper, structure earns as many marks as knowledge.

1

This is your last paper, use that

If you know a topic tripped you up on Paper 1 or 2, it is worth an extra 10 minutes of practice this evening. Paper 3 samples the whole spec again, weak topics get a second chance to cost you marks or earn them back.

2

Substitute into the quadratic formula in stages

Write b squared, then minus 4ac, then the square root, then the two answers, as separate lines. Doing it all in one calculator button-mash is where sign errors creep in on a 3 or 4-mark question.

3

State the scale factor and centre of enlargement

An enlargement answer needs both a correctly drawn shape AND a stated scale factor and centre for full marks. Missing the written statement loses marks even with a perfect drawing.

4

Don't round early

Keep the full calculator display between steps in multi-step problems and only round your final answer to the accuracy asked for. This matters even more on a final paper where fatigue makes early rounding tempting.

5

Check the mark allocation before you start

A 5-mark algebraic fractions question needs roughly 5 distinct steps of working. If you have written one line and reached an answer, you have almost certainly missed something. Go back and check.

Avoid these

5 mistakes that cost marks

The errors examiners see most on this paper. Each one is an easy mark you already know how to keep.

Forgetting the negative sign when finding a perpendicular gradientIf a line has gradient m, a perpendicular line has gradient -1/m. Flip the fraction AND change the sign, both steps are needed

Enlarging by a fractional scale factor as if it were a normal enlargement (making the shape bigger instead of smaller)A scale factor between 0 and 1 shrinks the shape. A negative scale factor flips it through the centre of enlargement. Sketch what should happen before you draw

Finding a common denominator incorrectly when adding or subtracting algebraic fractionsMultiply the two denominators together to find a common denominator, just as with numerical fractions, then adjust each numerator to match

Substituting values into the quadratic formula with sign errors, especially when b or c is negativeWrite out b squared, minus 4ac, and the square root as separate lines rather than doing the whole calculation in one go on your calculator

Using the wrong angle sum for interior or exterior angles of a polygonExterior angles of any polygon always sum to 360 degrees. Interior angles sum to (n-2) x 180 degrees, where n is the number of sides. Learn both formulae separately

Exam day

The morning of the exam

The 60 minutes before you walk in. Review what you know and settle your nerves.

  • Check your calculator has working batteries, and a spare set if you can manage it
  • Bring pen, pencil, ruler, protractor, compasses even on a calculator paper, geometry questions still need them
  • Remind yourself of the quadratic formula and the negative reciprocal rule for perpendicular gradients, both are quick to forget under pressure
  • Read every question twice before writing. On a final paper, tiredness makes it easy to answer the question you expected rather than the one that was asked
  • Attempt every question, even partially. A method mark for a half-finished answer beats a blank box
  • Leave your last 5 minutes to check unanswered questions, not to redo ones you have already completed

Now test yourself

You do not revise maths by reading it. Work exam-style questions in PrepWise, get them marked instantly, and see exactly which topics still cost you marks.

Practise Maths questions

Start the 3-day plan now

Open the Maths Knowledge Organisers, quiz every priority topic and walk in ready. Free during alpha.

Get started with your personalised revision
Get started with your personalised revisionStart here