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# help with conditional expectation watch

1. if we have a crooked coin, with P(H)=0.55 and P(T)=0.45. Then what is the difference between finding E(X) and E(Y) . Given X is the number of coin tosses until 2 successive heads (HH) occur and Y is the number of coin tosses until a head is immediately followed by a tail (HT)
does a crooked coin effect the method of finding E(Y) different from finding E(X) due to the chance of getting heads is more likely than getting tails ?
2. (Original post by vanessa_tram)
if we have a crooked coin, with P(H)=0.55 and P(T)=0.45. Then what is the difference between finding E(X) and E(Y) . Given X is the number of coin tosses until 2 successive heads (HH) occur and Y is the number of coin tosses until a head is immediately followed by a tail (HT)
does a crooked coin effect the method of finding E(Y) different from finding E(X) due to the chance of getting heads is more likely than getting tails ?
Duplicate in the maths forum.

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