Brain Test 1 Level 17
What is the hidden number
Drag the stone, the hidden number is 40.

Follow the screen sequence
Use the images as a compact replay of the solving path. The text below each frame explains what should change.

Video walkthrough
Same number in other versions
Brain Test versions can reuse the same level number with a different puzzle. If the screenshot or question does not match your game, switch to the same number in another version or use the nearby level links.
Strategy guide
- 1.Drag the stone left or right to uncover the hidden number beneath it;
- 2.Focus on interactive elements; the stone is movable, not just decorative;
- 3.After moving the stone, the number 40 will be visible on the ground.
Common mistakes
- 1.Tapping the stone instead of dragging it to reveal the number;
- 2.Looking for numbers in the background or text instead of under the stone;
- 3.Assuming the answer is a single digit like 4 or 0, not 40.
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