G3 Mathematics (K310), was O-Level E-Math (4052)
O-Level E-Math formula sheet
The E-Math paper prints a short list of formulas on its second page. Below is every formula on that list, with a worked example for each, and then the longer list the paper does not give you: the quadratic formula, every area and volume outside the list, gradients, indices, probability and the circle properties.
O-Level E-Math formula sheet
G3 Mathematics (K310), was O-Level E-Math (4052)
Given in the exam
SEAB prints these at the front of every paper. Know what each letter means and when to use each one, so you are not reading the list for the first time on the day.
Compound interest
Total amount
r is the rate for one period and n the number of periods.
Example: $5000 at 3% a year for 2 years: 5000 × 1.03² = $5304.50.
Mensuration
Curved surface area of a cone
Example: r = 3 cm, slant height l = 5 cm: 15π ≈ 47.1 cm².
Surface area of a sphere
Example: r = 2 cm: 16π ≈ 50.3 cm².
Volume of a cone
Example: r = 3 cm, h = 4 cm: 12π ≈ 37.7 cm³.
Volume of a sphere
Example: r = 3 cm: 36π ≈ 113 cm³.
Area of a triangle
C is the angle between sides a and b.
Example: a = 8 cm, b = 5 cm, C = 30°: ½ × 8 × 5 × 0.5 = 10 cm².
Arc length
θ in radians.
Example: r = 6 cm, θ = 1.2 rad: 7.2 cm.
Sector area
θ in radians.
Example: r = 6 cm, θ = 1.2 rad: ½ × 36 × 1.2 = 21.6 cm².
Trigonometry
Sine rule
Use it when you know a side and the angle opposite it.
Example: a = 10 cm, A = 40°, B = 65°: b = 10 sin 65° ÷ sin 40° ≈ 14.1 cm.
Cosine rule
Use it for two sides and the angle between them, or for three sides.
Example: b = 5 cm, c = 7 cm, A = 60°: a² = 25 + 49 − 35 = 39, so a ≈ 6.24 cm.
Statistics
Mean
For grouped data, x is the mid-value of each class.
Example: Scores 1, 2, 3 with frequencies 2, 5, 3: Σfx = 21, Σf = 10, mean = 2.1.
Standard deviation
Example: Same data: Σfx² = 49, so √(4.9 − 2.1²) = √0.49 = 0.7.
Not given: learn these by heart
The paper does not print any of these, and the questions expect you to know them.
Numbers, percentage and rate
Simple interest
Example: $2000 at 4% a year for 3 years: I = $240.
Percentage change
Example: 80 rises to 92: 12 ÷ 80 × 100% = 15% increase.
Reverse percentage
Example: $64 after 20% off: 64 ÷ 0.8 = $80 before.
Standard form
Example: 0.000 52 = 5.2 × 10⁻⁴.
Laws of indices
Example: 8^(2/3) = (∛8)² = 2² = 4.
Speed
Example: 72 km/h ÷ 3.6 = 20 m/s.
Direct and inverse proportion
Example: y = k/x and y = 6 when x = 2, so k = 12; when x = 3, y = 4.
Map scale
Example: 1 : 50 000 means 1 cm to 0.5 km, so 1 cm² to 0.25 km².
Algebra
Special products
Example: 51² − 49² = (51 + 49)(51 − 49) = 200.
Quadratic formula
Not on the E-Math list. The A-Math list has it; this paper does not.
Example: x² − 3x − 1 = 0: x = (3 ± √13) ÷ 2, so x ≈ 3.30 or −0.303.
Completing the square
Example: x² + 6x + 1 = (x + 3)² − 8, so the minimum point is (−3, −8).
nth term of a linear sequence
Example: 5, 8, 11, ...: a = 5, d = 3, so Tₙ = 3n + 2.
Coordinates and graphs
Gradient
Example: (1, 2) and (4, 11): m = 9 ÷ 3 = 3.
Length of a line segment
Example: (1, 2) and (4, 6): √(9 + 16) = 5.
Straight line
c is where the line crosses the y-axis.
Example: Gradient 3 through (0, −2): y = 3x − 2.
Angles, triangles and circles
Pythagoras' theorem
c is the side opposite the right angle.
Example: Sides 6 cm and 8 cm: hypotenuse = √100 = 10 cm.
Trigonometric ratios
Right-angled triangles only.
Example: Hypotenuse 10 cm, angle 30°: opposite = 10 sin 30° = 5 cm.
Angles of a polygon
Example: A regular hexagon: each exterior angle 360° ÷ 6 = 60°, each interior angle 120°.
Circle properties
O is the centre and C is on the circle. Also: angles in the same segment are equal, and tangents from one point are equal.
Example: An angle of 35° at the circumference stands on the same arc as 70° at the centre.
Similar figures
Example: Lengths 2 : 3 give areas 4 : 9 and volumes 8 : 27.
Mensuration
Plane figures
Example: A trapezium with parallel sides 5 cm and 9 cm, height 4 cm: 28 cm².
Prisms and cylinders
Example: A cylinder with r = 2 cm, h = 5 cm: V = 20π ≈ 62.8 cm³.
Volume of a pyramid
Example: A 6 cm square base, height 5 cm: ⅓ × 36 × 5 = 60 cm³.
Radians
Example: 1.2 rad = 1.2 × 180° ÷ π ≈ 68.8°.
Area of a segment
Sector minus triangle. θ in radians, and the calculator in radian mode.
Example: r = 6 cm, θ = 1.2 rad: 21.6 − 18 sin 1.2 ≈ 4.82 cm².
Unit conversions
Example: 3.5 m² = 35 000 cm².
Vectors
Magnitude
Example: The vector (3, −4) has magnitude 5.
Vector between two points
Example: A(1, 2) and B(4, 6): AB = (3, 4).
Statistics and probability
Median and quartiles
Example: 9 values in order: the median is the 5th.
Probability
Example: Two fair coins: P(two heads) = ½ × ½ = ¼.
Use the formulas on a paper
A free E-Math paper in the O-Level's two-paper shape for each year, with every answer, to print or sit online.
Questions parents ask
- Is this the official E-Math formula list?
- The first half has every formula on SEAB's list for G3 Mathematics (K310), set out in our own layout with our own examples. The paper prints the list at the front, so the second half, what it leaves out, is the part to learn. Scholar Tests is not connected with MOE, SEAB or Cambridge.
- Did the formula list change with the SEC?
- No. From 2027 the O-Level becomes the Secondary Education Certificate, and the subject is called G3. SEAB's 2027 syllabus has the same topics and the same formula list as the 2026 O-Level one, so this sheet serves both.
- How should answers be given?
- To 3 significant figures unless the question says otherwise, and angles in degrees to 1 decimal place. Use your calculator's π or 3.142, unless the answer is wanted in terms of π. Show the working: essential working left out loses marks.
- Can I print it?
- Yes. The print button gives both halves on plain paper, without this page's buttons or questions. Keep it beside you while you do past-year and practice papers until you no longer need to look.