How the DAT Next Generation Numerical Sequences test works
DAT Next Generation is a set of five separate ability tests, and the employer chooses which ones you sit. Numerical Sequences measures problem solving with numbers: reasoning from a pattern, not heavy arithmetic. The sums involved are simple. The work is in seeing the rule.
TalentLens does not publish the layout or the number of options. A number series question normally shows five or six numbers and asks for the next one.
There are 15 questions and no time limit, and most people take 10 to 12 minutes. The test is adaptive: a right answer brings a harder series and a wrong one an easier series. You must answer all 15 to receive a score.
How to find the rule in a number series
Try the rules in this order. Most series fall to one of the first three.
- Write the gap between each pair of neighbours underneath the series. A constant gap is the rule.
- If the gaps are not constant, look at the gaps themselves. Gaps of 3, 5, 7, 9 are a series of their own.
- If the numbers grow or shrink quickly, divide each by the one before. A constant ratio means multiplying, and a near-constant one means multiply then add or subtract.
- If the numbers rise and fall in turn, split the series into every second number. Two simple series are often woven together.
- Test your rule on every number in the series before you use it. A rule that explains only the last three terms is a coincidence.
Worked examples
- 5, 8, 13, 20, 29, ? The gaps are 3, 5, 7, 9, rising by 2 each time. The next gap is 11, so the answer is 40.
- 3, 7, 15, 31, ? The gaps are 4, 8, 16, doubling each time, so the next gap is 32 and the answer is 63. The same rule read another way: double the number and add 1.
- 2, 20, 4, 17, 6, 14, ? The numbers rise and fall, so split them. Positions one, three and five run 2, 4, 6. Positions two, four and six run 20, 17, 14. The missing number is in the first series, so the answer is 8.
How the test is scored
Everyone answers 15 questions, but not the same 15, so the number you get right says little. The test weighs each answer by the difficulty of its question and produces an ability score, which is reported as a percentile against a norm group the employer chooses. No pass mark is published.
Tips for the real test
- Write the gaps down every time. Seeing them on paper is faster than holding them in your head.
- When a series has seven or more numbers, suspect two series woven together.
- Do not settle for the first rule that produces one of the options. Check it against the whole series.
- There is no clock. If a series will not give, leave it for a minute, look again and start from the gaps.
- Finish all 15 in one sitting. An unfinished test gives no score.
Practise Numerical Sequences on CogniPrep
Our Numerical Sequences game gives you 15 generated number series with five options each. It adapts across three difficulty levels from a middle start, has no time limit and does not let you go back. Every series is checked so that only one simple rule fits it. Your result is an ability estimate with a percentile against other CogniPrep users. The five options and the difficulty levels are ours.