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10 questions · 10 min

Numerical Reasoning: The GAN Aptitude Test Section, Explained

Numerical Reasoning is the shortest section — 10 number-series questions in 10 minutes. You are shown a sequence and asked for the next term. A full minute per question sounds generous, and it is, provided you have a system instead of staring.

Questions
10
Time
10 min
Calculator
Not allowed

That is a full minute per question. This section is one of six on the battery, which runs about 140 questions in roughly two hours — see the full GAN aptitude test breakdown for how the whole thing fits together.

What this section measures

Pattern recognition under a clock: can you see structure in numbers rather than grinding at them. It is the closest thing on the battery to a raw reasoning measure.

Because the section is only 10 questions, every single item is worth more than an item anywhere else on the test. Two careless misses here move your ranking more than two misses in reading.

How to train it

Always write the differences first

Under the sequence, write the gap between each pair of terms. If the differences are constant it is arithmetic and you are done. If the differences themselves form a pattern, take differences again. This one habit solves the large majority of items without any cleverness.

Then test for a ratio

If the differences go nowhere, divide each term by the one before it. A constant ratio means a geometric sequence — 5, 15, 45, 135 is ×3, so the next term is 405. Growth that looks explosive is nearly always multiplication rather than addition.

Suspect two interleaved series

When a sequence alternates up and down, or when nothing works on the whole run, read every other term as its own series. 3, 20, 6, 17, 9, 14 is two sequences braided together: 3, 6, 9 climbing by 3 and 20, 17, 14 falling by 3.

Check the familiar families

Squares (1, 4, 9, 16, 25), cubes (1, 8, 27, 64), and add-then-double style recursions cover most of what is left. If a sequence looks like none of the above, take your best structural guess and move — one minute is the budget, and a tenth of the section is not worth three minutes.

Where applicants lose points

  • Finding a rule that fits the first three terms but not the fourth. Always verify your rule against every term shown, not just the start of the run.
  • Off-by-one errors on "what is the 8th term" questions — the 8th term of a sequence starting at 4 with difference 7 is 4 + 7x7 = 53, not 4 + 8x7.
  • Spending four minutes on the one item you cannot crack, then rushing three you could have had.

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Frequently asked

What is the numerical reasoning section of the GAN test?

Ten number-series questions in ten minutes. You are given a sequence of numbers and must supply the next one by identifying the underlying pattern.

How do you solve number series questions quickly?

Write the differences between consecutive terms first. Constant differences mean an arithmetic sequence; a pattern in the differences means take differences again; no pattern at all means test for a constant ratio, then for two interleaved sequences.

The other five sections

Ready to sit the whole thing? Take a free full-length practice test in the GAN format — timed sections, no calculator, instant scoring.

Drill Number Series until it is your best section

Reading about a section and scoring on it are different things. The app has ten full-length timed batteries plus dedicated number series drills, so test day is your eleventh run at it, not your first.

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