Apply the same row and column rule to the missing cell. Compare each option with the required features.
Solution diagram
1: B 2: B 3: A 4: B
Printed order
▸ Why It Matters Unlike other puzzles that change a discrete property like shape or count, this set isolates a single continuous quantity — a circle's diameter — as the only thing shifting from cell to cell. Because a circle has no corners, orientation, or color to distract from the one thing that matters, this is about as pure a way as exists to practice estimating a smoothly growing or shrinking amount. That skill — judging both which direction a quantity is moving and roughly how much it's changing by — is exactly what a child relies on later when reading a line graph, estimating a measurement between two marks on a ruler, or noticing that a recipe was scaled up "about double" rather than by some exact fraction. Estimating continuous quantities is a genuinely different mental muscle from counting discrete items, and it's one that a lot of children get far less practice with. ▸ Getting Started Before your child tries to guess an exact size for the missing circle, have them go cell by cell across the row and say only "bigger" or "smaller" compared to the one before it — nothing more precise yet. Locking in the direction of change first, cleanly and without hesitation, makes the harder next step of estimating how much bigger or smaller far more manageable, because they're no longer trying to solve both problems in the same glance. ▸ If They Get Stuck Pull out a handful of coins, buttons, or lids of different sizes and physically line them up next to the circles in the row, smallest to largest, so your child can see the actual size steps sitting side by side rather than trying to hold them all in memory. Once the real progression is laid out in front of them, estimating where the missing circle should fall in that lineup becomes a much more concrete, visual task instead of an abstract guess. ▸ Praise Points Praise your child specifically for noticing the size of the steps, not just their direction: "You didn't just say the circles keep getting bigger — you noticed they grow by about the same amount each time. That's a really precise, careful kind of noticing, and it's exactly the skill that makes it possible to read a graph accurately instead of just glancing at whether a line goes up or down."
Sharpens continuous-quantity reasoning by tracking a single smoothly changing property — a circle's diameter — and estimating both the direction and the amount of change.
Once smooth size changes feel intuitive, move to Matrix Reasoning 9 (Polygon Side Count) for a discrete version of the same increasing/decreasing skill, or Matrix Reasoning 14 (Pie Wedge Fractions) for proportional change.