Verbal Reasoning Number Series
The JUMPS method in under four minutes — one real question, solved step by step.
A Number Series question shows a row of numbers with a gap at the end. You find the number that continues the series.
The rule might add, take away, times or divide. And the row might be two series woven together, taking turns.
The video above and the worked example below take apart the same question. One thing is different: the video shows the five options in another order, so the answer, 19, is lettered E in the video and may carry a different letter here. Same number, different place in the line-up.
The method
Five steps: judge the row, untangle the two series, measure the jumps, push on one jump, step back to check — and their first letters spell JUMPS, because every series moves in jumps.
- Step 1 of 5
Judge the row
How long is it, and which way does it move? Four or five numbers is usually one series. A long row of seven, eight or nine numbers, or one that goes down, up, down, up, is the sign of two series woven together. - Step 2 of 5
Untangle the two series
Take every other number: the 1st, 3rd, 5th… make one series, and the 2nd, 4th, 6th… make the other. Count on to the gap to see which one it belongs to, and keep only that one. A short row is one series, with nothing to untangle. - Step 3 of 5
Measure the jumps
Between each pair of neighbours in your series, is it add, take away, times or divide? Is it the same jump each time, or does it grow, or take turns? Numbers that double or more each time point to times. - Step 4 of 5
Push on one jump
One jump only, from the last number in your series. That may not be the last number printed. - Step 5 of 5
Step back to check
Work back from your answer to the number before it. Then make sure the jump fits every gap, not just the last one, and find your number in the options.
About 30 seconds each.
Rules to watch
In GL's practice papers, half the questions keep one simple rule all the way along. The rest are two series woven together, or a jump that changes.
- One steady jump. The same amount added or taken away every time. These often go down, and the jump can be a big one.
- Times or divide. Times 2, times 3 or divide by 3, every time. Numbers that grow or shrink fast are the clue.
- Two series woven together. Every other number. Only the gap's series matters.
- A jump that changes. It grows (+2, +3, +4), takes turns (+3, +5, +3, +5), or is a times then a fix (×2 then +3).
Watch for these traps
We looked at all fourteen Number Series questions in GL's practice papers, and at how each wrong answer is built.
- The wrong answers sit right next to the right one. In 12 of the 14, a wrong answer is within four of the right one, so a number that looks about right proves nothing. Check by working back. In 10, 14, 19, 25, 32 the jumps grow by one, so the next jump is eight: 40. 39 just repeats the last jump, and every wrong answer is only one or two away.
- It might multiply or divide. Four of the fourteen need times or divide. Most of their wrong answers times or divide by the wrong number, or add or take away instead. In 50, 2, 47, 4, 44, 8, 41 the gap's series doubles: 2, 4, 8, then 16. Adding four would give 12, and 12 is offered too.
- Answer from the gap's own series. In three of GL's four two-series questions, the other series' next number is one of the options. A long row is two series even if it only goes down. In 50, 48, 47, 44, 43, 39, 38, 33, 32 the gap's series is 48, 44, 39, 33: down 4, 5, 6, so next is down 7, to 26. 25 is where the other series goes next, right beside it.
Stuck? Put each option into the gap in turn and see which one makes a pattern. It is slow, but it always finishes. Never leave a blank.
Try these yourself
Now have a go yourself — tap the number that comes next.
Related
- The complete 11+ question-type guide
- VR: Letter Series — the same "find the rule, carry it on" trick with letter pairs
- VR: Letter Analogies — apply a letter shift to a new pair
- VR: Complete the Sum — make both sides of an equals sign match
All example questions come from the Brainblox question bank — practise this question type inside 25+ learning games, timed mock exams and focused practice. Brainblox is an independent app: not affiliated with, endorsed by or licensed by any exam board, school or assessment publisher, and it contains no past papers.