Gacha Probability Survival
Probability Survival
Choose the door with the higher chance and survive each stage.
Choose a lower chance and your run ends!
Example: 2/8 (25%) is more likely than 1/5 (20%)Choices: 2 (Stages 1–10), 3 (Stages 11–20), then 4 (Stage 21+).
Choose a door with the highest chance to clear the stage.
“40% or higher” is a lower bound; “1/7 or lower” is an upper bound.
Checking…
Tap anywhere in this panel or use the button to skip.
GAME OVER
Title
Stage reached
Best streak
Overall survival rate
How to Play
- Press Start to begin.
- Compare the fractions and choose the door with the higher probability (the better chance).
- Choosing the highest probability clears the stage. A lower one ends your run.
- The denominator limit increases at stages 3, 6, and 10. You will choose from 3 doors starting at stage 11 and 4 doors starting at stage 21.
- When a mystery door appears, use its hint to compare the probabilities.
“40% or higher” means at least 40%. “1/7 or lower” means no more than about 14.3%. Treat the mystery hint as a lower or upper limit and compare it with the visible doors.
How to Compare Fractions
- Convert to percentages: numerator ÷ denominator × 100. 1/5 = 20%, while 2/8 = 25%, so 2/8 is more likely.
- Cross-multiply: for 1/5 and 2/8, compare 1 × 8 with 2 × 5. Since 8 < 10, 2/8 is greater.
- If both numerators are 1, the smaller denominator wins: 1/4 is more likely than 1/9.
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