Logical reasoning exercise · ~1 min a run · free
Number Series
Spot the rule, predict the next number.
Session mode
Difficulty
Auto sets the level from your recent results: up when you are acing it, down when it is too hard.
How to play
- 1Study the sequence and work out how each term changes.
- 2Predict the next number in the series.
- 3Select it from the options.
See a worked example
Take 3, 7, 12, 18, 25, ? Do not stare at the numbers themselves; write the gaps between them, because the rule almost always lives in the gaps rather than in the terms. Here they are +4, +5, +6, +7, which is a step that grows by one each time, so the next gap is +8 and the answer is 33. That one habit, differences first, covers most of what you will meet: equal gaps mean a constant step, gaps that grow mean an accelerating series, gaps that alternate mean two rules taking turns, and if the gaps look wild, check whether each term is a MULTIPLE of the one before instead. The trap is answering with the next gap rather than the next term, so finish by adding it back on.
Each sequence follows a hidden rule. Find the pattern and continue it. Number series test inductive reasoning, a core part of most pilot aptitude batteries.
About this test
About this test
What this test measures
This measures inductive reasoning: spotting the rule behind a sequence of numbers and extending it. It is a classic test of fluid intelligence, the raw problem-solving airlines value because learning new systems and procedures leans on it.
How to improve your score
- Look first at the differences between terms, then at the differences of those differences.
- Test for multiply, divide and alternating patterns when simple addition does not fit.
- If one rule does not work, switch hypothesis quickly rather than forcing it.
Good to know
Good to know
Write the gaps
Note the difference between each pair of terms. A constant gap is addition; a growing or repeating gap is a step or alternating rule; if the terms multiply, look at the ratios instead.Check two ways before you commit
Confirm your rule predicts a known term as well as the missing one. A rule that fits only part of the series is the wrong rule, and the options usually include the trap it leads to.
Frequently asked questions
What kinds of rules appear?
What kinds of rules appear?
What is a good strategy?
What is a good strategy?
Is this inductive or deductive reasoning?
Is this inductive or deductive reasoning?
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