Brain Out Level 108
📝 Walkthrough
Overview
The prompt asks for the minimum cuts needed to cut a circle into eight equal parts. A plain blue circle sits in the middle of the board above an Enter field and an OK button. On paper, dividing a flat circle into eight equal wedges usually takes three straight cuts, but this level allows folding the circle first. Folding stacks the parts on top of one another, so a single cut through the folded layers produces eight equal pieces when unfolded. The answer to enter is one.
- Difficulty: Easy
- Estimated moves: 1
Step-by-Step Solution
- Read the question and note that it asks for the minimum cuts, not the minimum cuts while the circle lies flat on the table. The word minimum invites you to look for any preparation that reduces the number of strokes.
- Imagine folding the circle along its center lines. Fold it in half once, then fold it in half again, and a third time so all eight wedge sectors stack on top of one another in a small folded packet. Each fold doubles the number of layers piled together.
- Recognize that one straight cut through this stacked packet slices through every layer at once. When the circle unfolds, those layers become eight equal wedges arranged around the center.
- Compare this with cutting the circle unfolded. Three perpendicular or radial cuts would be needed to divide a flat circle into eight sectors, but folding removes that limitation because the stacked layers share a single stroke.
- Conclude the minimum number of cuts is one. The single scissor stroke reaches all eight sectors only after the three folds are made, so the answer counts cuts rather than folds.
- Tap the Enter field, type 1, and press OK. The level accepts the single-cut answer and shows the success panel. If the entry is rejected, reconfirm that one cut can pass through all folded layers rather than counting the folds themselves as cuts.
Strategy & Reasoning
The word "minimum" opens the door to a non-obvious operation. Standard geometry counts straight cuts across a fixed sheet, but Brain Out lets you manipulate the circle before cutting, and folding is the classic way to reduce the number of scissor strokes. Each fold doubles the number of layers, so after three folds eight layers align, and one cut reaches all of them.
Answering three comes from assuming the circle cannot be folded; that is the expected intuition the level pushes against. Answering four or more comes from counting layers rather than cuts, but each scissor stroke passes through every stack. The puzzle therefore rewards thinking about what physical preparation is allowed before the first cut, rather than drawing radial lines on the circle itself.
Tips & Common Mistakes
- Do not answer three radial cuts; that is the flat-circle solution, and folding the circle cuts that count down to one.
- Remember the cut passes through all folded layers at once, so one stroke makes eight pieces after unfolding.
- Enter 1 and press OK; if a larger cut count is rejected, re-check the folding assumption rather than adding more cuts.