system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Math! If something has a one-in-a-million chance, how likely is it to happen at least once in a million chances?

I can't figure out a way to figure this, or other probability questions with big numbers, out using normal math. So what am I missing? What are the principals of sorting out a question like this?
gpt
The basic idea is to take the chance of it NOT happening x times in a row, and subtract it from 1. The chance of it not happening is 999,999/1,000,000. So the chance of it happening in 1,000,000 tries is 1 - (999,999 / 1,000,000)^1,000,000 = 0.63. There's a 63% chance it will happen in 1,000,000 tries.