Eli5: How do the odds of flipping a coin work?

725 views

I know, 50/50 heads tails right? But help me understand the next step – each coin flip has a 50/50 shot of heads or tails. What I don’t understand is how the likelihood of the next flip doesn’t change. For example if I flipped a coin 10 times and every time it flipped heads, the next flip would be 50/50 tails. Wouldn’t the likelihood of flipping a coin 11 times and having it be heads every time be really low? 0.5^11 = 0.048%?

Here’s the origin of the question. I was at a roulette table and the guy said “it’s been black the last 8 rolls, the next one has to be red.” At first I thought, the next roll will be ~47% black, ~47 red, ~6% 0 or 00 you fucking imbecile. Then I thought to myself, what are the chances that there are no red rolls in 9 rolls, which is well below 1%.

Am I the imbecile?

In: 215

40 Answers

Anonymous 0 Comments

50/50 just means that half the tries are being one result.

But of how many tries?

It can be 5 of 10, 500 of 1000 or even 500m of 1b.

There was once a case in 1913 in the Monte Carlo Casino.

There was a roulette game going on with the ball falling 26 times in a row on black, even though the chances are ~50%.

You are viewing 1 out of 40 answers, click here to view all answers.