Numerical Reasoning
Arithmetic series, ratios, quantitative logic
What this sub-test measures
Numerical reasoning evaluates how efficiently you manipulate quantitative relationships under time pressure. Items resemble the ICAR Letter and Number Series subtest and the numerical sections of the Wechsler Adult Intelligence Scale (WAIS-IV). The skill draws on both crystallized knowledge — memorized arithmetic facts and number sense — and fluid reasoning, the ability to detect the operation that links one term to the next without prior exposure to the specific sequence. Strong performers convert the surface form of a problem into the smallest possible mental representation before searching for a rule: they compute first differences, look for ratios, and check whether a sub-sequence repeats. Numerical reasoning loads heavily on g but is moderately separable from spatial and verbal abilities, which is why most modern test batteries score it as its own subtest.
Strategy notes
- Compute first differences before assuming a multiplicative rule — addition is more common than multiplication in well-designed items.
- Flag any term that breaks the obvious trend — that term is usually the diagnostic clue.
- Round large numbers to the nearest power of ten for a sanity check before submitting.
- When two rules seem to fit, prefer the simpler one (Occam-friendly items dominate published banks).
- Practice multiplication tables to free up working-memory slots for the rule-search itself.
Sample items from this domain
Item #21
What number completes the series?
View itemItem #22
What number completes the series?
View itemItem #23
What number completes the series?
View itemItem #24
What number completes the series?
View itemItem #25
What number completes the series?
View itemItem #26
What number completes the series?
View itemTraining drills for this domain
Number Series Sprint
10 min
Mixed Numerical Series
20 min
Mental Arithmetic Drills
15 min
Number-Bonds Drill
10 min
Mental Fractions and Percentages
20 min
Improve Numerical Reasoning
See the brain-training guide for Numerical Reasoning →
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