Gacha Probability Survival

STAGE —
STREAK 0
BEST 0
🎰

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.

日本語版はこちら

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