Probability question of flipped coins

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SUMMARY

The probability of obtaining the specific sequence HTHHTTTHTHHHTHHHHTHT when flipping 20 fair coins is calculated by recognizing that there is only one successful outcome for that exact order. The total number of possible outcomes when flipping 20 coins is 2^20. If the order does not matter, the number of successful outcomes is given by the combination formula C(20,12), which represents the number of ways to choose 12 heads from 20 flips. Thus, the probability of the specific sequence is 1/2^20, while the probability of getting 12 heads in any order is C(20,12)/2^20.

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Homework Statement



suppose you flip 20 fair coins. what is the probability of getting the sequence HTHHTTTHTHHHTHHHHTHT in exactly that order?

What if the order doesn't matter?

Homework Equations





The Attempt at a Solution


Ok so in general the total possible outcomes are 2^20.
and the #ways you can get 12 H (or the multiplicity) would be 20!/(12!(20-12)!) right?
i don't how how to account for the order, or switch it to probability
 
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You know everything you need to know. There are 2^20 possibilities. If you account for order, there's only one way to succeed. If you don't there are C(20,12) ways, as you said. The probability is the number of ways to succeed over the total number of possible ways.
 

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