Non-Verbal Reasoning Series
A series is a row of five boxes. A hidden rule turns each box into the next. One box is empty, and you pick the figure that belongs there.
The empty box is often not the last one, so find it first. And expect two or three rules running at once, not one. That is what makes the hard ones hard.
The method
Five steps: find it, pair it, follow it, fill it, check it.
- Find it. Find which box is empty. If the gap is box 1, run the series backwards. If it is in the middle, work out the step between the boxes on either side.
- Pair it. Look at two boxes that sit next to each other and work out what changes between them. Those are the rules. Stuck? Run the SHAPES+S scan below.
- Follow it. Check each rule holds across the rest of the row. A shape might go black, white, black, white, for example.
- Fill it. Apply every rule into the gap, then look for the option that matches.
- Check it. Check one rule at a time, your answer must fit them all. Unsure? Cross out every option that breaks a rule, until one is left.
About 25 to 30 seconds for each question. Easy ones take 10, so bank that time for the hard ones.
💡 Worked example
Which figure completes the series (replaces the ?)?
How to answer
Rules to watch
When nothing jumps out, scan the SHAPES+S.
- S — Shade. White, grey, hatched (thin diagonal lines) or black? The most common change of all. Shades swap, or one shape hands its shade to another. Judge a tone against the figure next to it, not from memory.
- H — How many. Count them. A shape can appear, vanish, split, double, or copy itself to each side.
- A — Angle. A quarter turn clockwise, a half turn, or reflected — flipped over like a mirror? Watch one corner. A turn walks it round the shape. A mirror jumps it straight across.
- P — Place. Moved, traded jobs, or gone inside? A small item becomes the big frame, the middle swaps with the corners, loose shapes tuck into containers, a whole ring shifts one place clockwise.
- E — Edges. A different shape? More sides? A solid line gone dashed?
- S — Size. Bigger or smaller?
- +S — Symmetry. Does the figure fold onto itself? Down the middle, across the middle, or the same upside-down. Fold the whole figure, not just its outline. Symmetry is rare in this type of question — check it last if all others fail.
Then two questions this type asks and no other does.
- How fast is each clock? They rarely match. The big shape may repeat every three boxes while a marker swaps every two. Count each one on its own fingers. "Shape: 1, 2, 3, 1, 2. Marker: 1, 2, 1, 2, 1."
- Does it come back round? Turns do, and so do fill cycles and walks round the corners: after three-quarters comes a whole turn, then it starts again. Sizes and counts do not. They just keep going.
Watch for these traps
Every wrong figure obeys most of your rules and breaks exactly one, on purpose. A figure that matches the rule you found proves nothing. Check every rule on every option.
- One clock stopped. Much the most common: every rule stepped on but one. Count your rules, then find each on the figure.
- The right change on the wrong part. The move happened, to the wrong dot or corner or shape. Point at the part in the last box, then in the option.
- The wrong way round. Turned anticlockwise, shaded on the other side, or the arrow points back. Put a direction in your rule.
- One too many, or one too few. The count moved when it should have stayed, or stayed when it should have moved. Count the parts, do not judge by how full it looks.
- One step too far. The rule applied twice. Tempting, because the rule really is right. Say it out loud and step it on once.
- A box you can already see. It looks right because it is right, one step early or late. Cover the row before you choose.
Try these yourself
Now have a go yourself — tap the figure that completes the series.
✏️ Question 1
Which figure is missing?
The answer is option D
Two clocks. The triangle and the circle swap places every step, and the black dot hops to the next corner, always the same way round. Trap: the dot moved and the shapes forgot to swap.
✏️ Question 2
Which figure is missing?
The answer is option D
Three clocks, and the gap is box 1, so run all three backwards from box 2. The triangles change by one, the small square swaps black and white, and it moves one place round the edge midpoints. Traps: the wrong number of triangles, and the square the wrong colour.
✏️ Question 3
Which figure is missing?
The answer is option D
Two clocks, each with its own direction. The arrow turns a quarter at a time and the odd corner moves on one place. Traps: the arrow turned and the corner did not, and the odd corner put opposite instead of next.
✏️ Question 4
Which figure comes next?
The answer is option C
Three clocks at three speeds. The big shape repeats every three boxes, so the hexagon is back. The token swaps circle and triangle every box, so it is a circle. The token steps clockwise left, top, right, bottom, so it is back on the left. Each wrong figure breaks exactly one of those three. Answer: a hexagon with a circle on the left.
Related
- The complete 11+ question-type guide
- NVR: Analogies — the same rule, shown once instead of four times
- NVR: Matrices — a series in a box, running two ways at once
All example questions come from the Brainblox question bank — practise this question type inside 15 arcade 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.