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A math puzzle

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jamieyelloCreated:
jamieyello#1
https://www.youtube.com/watch?v=aHU-L3BLd_w He flips the coin 10 times in a row to get the pattern (heads and tails) HTHTHTHTHT. How many times did he flip the coin?
Yolkai#2
"1 in 1000" lol no it's 1 in 2 I stopped watching after that.
haloopdy#3
He flips it 10 times DUH! Lumage you're either wrong or being silly, it's 2^-10 which is indeed about 1 in 1000 (1 in 1024). The chances of getting any particular sequence of uniformly random values is k^-n where k is the number of choices (2) and n is the size of the sequence (10). The chance of getting 5 heads and 5 tails in any order is different than an exact order like in the video. For instance, the chance of getting this guy's sequence is the same as getting all heads or all tails.
Yolkai#4
Lumage you're either wrong or being silly, it's 2^-10 which is indeed about 1 in 1000 (1 in 1024).
It seems I misheard it, I thought he made a big deal about the ONE 9th flip being a 1 in 1000 in chance. Edit: Which should have been a hint to me because 2^9 is definitely not 1000 lol
haloopdy#5
The fun part is calculating approximately how many times he would actually have to flip it, CONSIDERING he doesn't flip it all 10 times if he messes up somewhere in the middle. For instance, if he messes up on the third throw, he can just immediately start again without having to complete 10 flips. Furthermore, if the messed up flip happens to be a head, he COULD theoretically start FROM that flip, but I'm guessing he doesn't considering he needs to start that part of the video with "this is number one" or something.
jamieyello#6
The fun part is calculating approximately how many times he would actually have to flip it, CONSIDERING he doesn't flip it all 10 times if he messes up somewhere in the middle. For instance, if he messes up on the third throw, he can just immediately start again without having to complete 10 flips. Furthermore, if the messed up flip happens to be a head, he COULD theoretically start FROM that flip, but I'm guessing he doesn't considering he needs to start that part of the video with "this is number one" or something.
I didn't make that assumption, I assumed that he could have started from TT HT TH or HH his goal being to make a video on "ten correct coin flips". That would lower it from 1/2^10 to 1/2^8. There's a jump cut, he doesn't mention how he's going for HTHT until he gets past the first couple flips, and lastly he mentions how easy the first couple are, those all feel like clues.