At first glance, this 3D cube structure looks straightforward. But the real challenge? Spotting what’s not there. The image shows a cube with a chunk missing—almost like steps carved out of its corner. And the question is simple, yet surprisingly tricky: How many small cubes are missing to make this a complete cube?
Before you scroll for the answer, stop. Take a close look. Try to mentally “fill in” the missing part. How many do you count? 15? 24? More? Less? Let’s put your brain to the test!
Why So Many People Get This Wrong
Visual illusions and 3D puzzles like this one often trip people up because our brains love to shortcut. We see patterns, assume symmetry, and estimate rather than calculate. This can lead to common errors like:
- Miscounting how many layers the cube has
- Forgetting to consider the depth of each missing step
- Only counting what’s visible from the front or side, but not the full structure
That’s what makes this kind of brain teaser so engaging—it forces you to slow down and really think in 3D.
Step-by-Step Breakdown to Solve It
Let’s walk through this together step by step and figure out how many cubes are actually needed to complete the full structure.
Step 1: Understand the Total Shape
This is supposed to be a perfect cube. So how big is that cube?
Count the number of small cubes along one edge. From the image, we can see:
- 5 cubes along the width
- 5 cubes along the height
- 5 cubes along the depth
So, the original full cube is 5 × 5 × 5 = 125 cubes.
Step 2: Count the Cubes That Are Already Present
Instead of counting all the cubes one by one, it’s easier to count how many layers are fully visible and how many are partial.
Video : How many Cubes are there
The bottom layer (level 1) is complete, so it has 25 cubes (5×5).
The second layer (level 2) has 20 visible cubes (a 5×4 rectangle).
The third layer (level 3) has 15 cubes (5×3).
The fourth layer has 10 cubes (5×2).
The top layer has just 5 cubes (5×1).
Now add those up:
25 + 20 + 15 + 10 + 5 = 75 cubes currently in place
Step 3: Subtract to Find the Missing Cubes
If the full cube should have 125 cubes, and only 75 are visible, that means:
125 – 75 = 50 missing cubes? Not quite.
Wait. Here’s the catch: in a cube structure like this, not all missing spaces are visible from the outside. Some are hidden behind other cubes.
That’s why a better method is to count what’s visibly missing in the cut-out section.
Let’s do it layer by layer:
- Top layer (layer 5): Missing 4 cubes
- Layer 4: Missing 3 cubes
- Layer 3: Missing 3 cubes
- Layer 2: Missing 5 cubes
- Layer 1: Missing 5 cubes
Now add: 4 + 3 + 3 + 5 + 5 = 20 missing cubes
And there’s your answer.
Correct Answer: 20 cubes are missing.
So… Did You Get It Right?
If you did, great job! Your brain is wired for spatial logic. If you didn’t, don’t worry—you’re definitely not alone. These puzzles are designed to trick your instincts, not measure your intelligence.
Video : The Ultimate Math Quiz! ➗✖️ | Easy, Medium, Hard & Impossible Levels
What matters is that you trained your brain to think more analytically and visualized the structure in 3D. That’s some serious mental exercise.
Join the Puzzle Party
Now it’s your turn to join the fun. Drop your answer in the comments and let us know—did you guess 20 correctly, or were you tricked by the visual illusion?
Tag a friend and challenge them to solve it too. See who’s the real 3D thinker in your circle!
Conclusion
Puzzles like this remind us that what you see isn’t always the full story. With a bit of patience and the right perspective, you can piece things together—literally. The next time you see a “simple” question, remember: sometimes, the missing pieces are the ones that teach you the most.
Keep puzzling. Keep learning. And always keep that curiosity alive. 🧠✨
