Mathematical Ability
What is measured
Straightforward school-level mathematics under time pressure: arithmetic with fractions and decimals, order of operations, ratio and proportion, percentages, averages, rates (speed, distance, work), simple algebra, basic geometry (area, perimeter, angles) and number properties such as factors, multiples and primes.
Traps to expect
- Order of operations. Multiplication and division before addition and subtraction; brackets first.
- Dividing by a fraction. Dividing by one half doubles the value - a common slip.
- "Less than" in algebra. "Five less than x" is x − 5, not 5 − x.
- Average speed. It is total distance over total time, never the mean of the two speeds.
- Work rates. Combine rates by adding reciprocals of times, not by averaging times.
- Perimeter versus area, and mixed units (cm with m, minutes with hours).
Worked example
A car covers 60 km at 60 km/h and a further 60 km at 30 km/h. The naive answer, 45 km/h, is wrong. Total distance is 120 km; total time is 1 h + 2 h = 3 h; average speed is 120 ÷ 3 = 40 km/h.
Rule of thumb
Estimate the answer before calculating, then substitute your result back into the original wording to confirm it satisfies every condition given.