Quantitative Skills
What This Section Tests
Quantitative Skills checks number sense and reasoning rather than heavy computation: number series, quantitative comparisons, estimation, and word problems involving rates, percents, and proportions.
Concepts to Know
- Sequences: look for a constant difference (arithmetic), a constant multiplier (geometric), or alternating/pattern rules (add 2, multiply 3, add 2...).
- Quantitative comparison: you compare two quantities, not solve for an exact value. Estimate when exact math is slow.
- Percents and proportions: part = percent × whole; set up ratios as fractions and cross-multiply.
- Averages: total = average × number of items. This unlocks most average problems.
- Rates: distance = rate × time; work problems add rates.
Traps to Watch
- Unit mismatches. Minutes versus hours, cents versus dollars - convert before computing.
- Percent increase vs. percent of. "Increased by 20%" multiplies by 1.20; "is 20% of" multiplies by 0.20.
- Misreading comparisons. Read which quantity is larger carefully; a small difference still decides the answer.
- Over-computing. If both quantities are clearly far apart, estimate and move on.
Rule of Thumb
For any series, first check differences between consecutive terms. If differences are constant, you have an arithmetic sequence; if ratios are constant, geometric. If neither, check alternating terms.
Worked example: Find the next term: 3, 6, 12, 24, ___. Differences are 3, 6, 12 - not constant. Ratios are 2, 2, 2 - constant. The next term is 24 × 2 = 48. Checking ratios first would have saved time.
Budget your time: skip a stubborn problem, finish the easy ones, then return.