Examiner Tips

Many candidates lost marks by not showing the factorisation step before solving. Writing "x = 3 or x = -2" without showing "(x - 3)(x + 2) = 0" loses the method mark.

0580/42 Nov 2023 Examiner Report

When using the quadratic formula, candidates frequently made sign errors. Write out a, b, and c separately before substituting into the formula.

0580/42 Jun 2023 Examiner Report

Candidates who attempted to cross-multiply before finding a common denominator often introduced errors. Find the LCM of the denominators first.

0580/42 Jun 2022 Examiner Report

When eliminating a variable, many candidates forgot to change the sign when subtracting equations. Check by substituting both values back into the original equations.

0580/22 Nov 2022 Examiner Report

For the nth term of a quadratic sequence, many candidates only found the linear part. The second difference must be used: if second differences are constant at d, the coefficient of n² is d/2.

0580/42 Jun 2023 Examiner Report

When the subject appears in more than one term, candidates must factorise to isolate it. Simply "moving terms" without factorising is a common error.

0580/42 Nov 2022 Examiner Report

Candidates must state the geometric reason, not just calculate the answer. "Angle in a semicircle = 90°" earns the reason mark; just writing "90°" does not.

0580/42 Jun 2023 Examiner Report

Bearings must always be given as three-figure values measured clockwise from North. "45°" should be written as "045°". Many candidates lost marks by omitting the leading zero.

0580/22 Nov 2023 Examiner Report

For a full description of a transformation, state ALL required elements: Rotation needs centre, angle, and direction. Enlargement needs centre and scale factor. Translation needs the column vector.

0580/42 Jun 2022 Examiner Report

For similar triangles, candidates should clearly identify corresponding sides and show the ratio calculation. Simply stating "the triangles are similar" without showing the scale factor loses marks.

0580/42 Nov 2023 Examiner Report

When finding angles, always state the reason for each step. "Angles on a straight line = 180°", "Vertically opposite angles are equal", "Alternate angles are equal" — the reason carries marks.

0580/22 Jun 2023 Examiner Report

Vector paths must follow a consistent direction. Many candidates wrote a + b when they should have written a - b. Trace the route on the diagram, noting when you travel against the arrow direction.

0580/42 Jun 2023 Examiner Report

Construction arcs must be visible. Candidates who erased their arcs lost the method mark. Leave all construction marks clearly showing.

0580/22 Jun 2022 Examiner Report

Rounding errors in currency questions cost many marks. Always use at least 4 decimal places in working, then round only the final answer to 2 d.p.

0580/22 Jun 2023 Examiner Report

For reverse percentage problems, many candidates calculated a percentage of the given value instead of dividing. If an item costs $120 after a 20% increase, the original is 120 ÷ 1.2 = $100, not 120 × 0.8.

0580/22 Nov 2022 Examiner Report

Candidates must express standard form correctly: a × 10ⁿ where 1 ≤ a < 10. Writing "23.5 × 10³" instead of "2.35 × 10⁴" is marked as incorrect.

0580/22 Jun 2022 Examiner Report

For upper and lower bounds, the most common error was using the wrong bound for division. To maximise a ÷ b, use the upper bound of a and the lower bound of b.

0580/42 Nov 2023 Examiner Report

When ordering fractions and decimals, convert everything to the same form first. Many candidates made errors comparing fractions with different denominators without finding a common denominator.

0580/12 Jun 2023 Examiner Report

Candidates frequently confused negative and fractional indices. Remember: a⁻ⁿ = 1/aⁿ and a^(1/n) = ⁿ√a. Write the rule before applying it.

0580/42 Jun 2023 Examiner Report

When sharing an amount in a ratio, many candidates forgot to find the total number of parts first. Always add the ratio parts before dividing.

0580/22 Jun 2023 Examiner Report

For inverse proportion, candidates often wrote y = kx instead of y = k/x. Read the question carefully: "y is inversely proportional to x" means y × x = k.

0580/42 Nov 2022 Examiner Report

In compound measure questions, always check your units match. Converting hours to minutes (or vice versa) was the most common source of incorrect answers.

0580/22 Jun 2022 Examiner Report

When simplifying ratios, both sides must be divided by the same number. Several candidates incorrectly simplified 12:8 to 6:2 instead of 3:2.

0580/12 Nov 2023 Examiner Report

In histograms, the y-axis must be labelled "Frequency density", not "Frequency". Frequency density = Frequency ÷ Class width. Many candidates plotted frequencies directly and lost all marks.

0580/42 Jun 2023 Examiner Report

For cumulative frequency diagrams, plot points at the UPPER boundary of each class interval, not the midpoint. Connect with a smooth curve, not straight lines.

0580/42 Nov 2022 Examiner Report

For combined events, draw a tree diagram and multiply along branches. Many candidates added probabilities when they should have multiplied. P(A and B) = P(A) × P(B) for independent events.

0580/42 Jun 2022 Examiner Report

When finding the mean from a frequency table, candidates must multiply each value by its frequency before summing. Dividing by the number of rows (not total frequency) was a very common error.

0580/22 Jun 2023 Examiner Report

Check your calculator is in DEGREE mode, not radians. This caused many completely incorrect answers in trigonometry questions. The answer should make sense in context.

0580/42 Jun 2023 Examiner Report

The sine rule finds sides/angles when you have a matching pair (angle + opposite side). The cosine rule is for when you have two sides and the included angle (or all three sides). Choosing the wrong rule wastes time.

0580/42 Nov 2023 Examiner Report

Many candidates subtracted instead of adding when finding the hypotenuse, or added instead of subtracting when finding a shorter side. Draw the triangle and label which side is the hypotenuse.

0580/22 Jun 2022 Examiner Report

For 3D trigonometry, always identify the right-angled triangle within the solid shape first. Sketch it separately before applying SOHCAHTOA or Pythagoras.

0580/42 Nov 2022 Examiner Report