Mathematics and Science
What the domain tests
Mathematics and Science carries 60 marks for candidates choosing this specialisation. It samples Classes VI–VIII content-number, algebra, geometry, mensuration, data handling; food, materials, motion, light, electricity, living organisms, health and environment-and tests pedagogical content knowledge.
Core rules
- Fractions: find a common denominator before adding; multiply numerators and denominators; divide by multiplying by the reciprocal.
- Percentage: part = percentage × whole; percentage change = change/original × 100.
- Algebra: balance equations by inverse operations; check by substitution.
- Geometry: angle sum of a triangle is 180°; Pythagoras applies only to right triangles.
- Science: control variables in experiments; distinguish observation from inference; use SI units; test acids/bases with indicators, not taste.
- Pedagogy: elicit misconceptions, use inquiry and locally available materials, and assess process skills, not only answers.
Worked example
A bus covers 120 km in 2 hours and 180 km in 4 hours. Average speed = total distance ÷ total time = (120 + 180) ÷ (2 + 4) = 300 ÷ 6 = 50 km/h. Averaging 60 km/h and 45 km/h gives 52.5 km/h, which is wrong because the times differ.
Traps
Convert units before calculating; check whether the question asks area or perimeter. LCM and HCF are not interchangeable. Pythagoras cannot be used without a right angle. In science, mass differs from weight, and a plant cell differs from an animal cell by its cell wall and chloroplasts.