Probability of letters in password

[Abe]

Hi, I have a tough problem here I am hoping someone can help me solve. I have a random 4 letter password and want to know the probability of having the letters AB, in that order be the first two letters. Not case sensitive.
Thanks

 

[Deleted member 4993]

Hi, I have a tough problem here I am hoping someone can help me solve. I have a random 4 letter password and want to know the probability of having the letters AB, in that order be the first two letters. Not case sensitive. Thanks

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[pka]

Hi, I have a tough problem here I am hoping someone can help me solve. I have a random 4 letter password and want to know the probability of having the letters AB, in that order be the first two letters. Not case sensitive.

Can letters be repeated? Do the A and the B need to be adjacent?

 

[Harry_the_cat]

Can the letters be repeated?

 

[Abe]

Can letters be repeated? Do the A and the B need to be adjacent?

The first two spots must be the letter 'A' followed by 'B' . The letters are next to each other in placement. The last two letters can be random 26 letters

 

[Deleted member 4993]

The first two spots must be the letter 'A' followed by 'B' . The letters are next to each other in placement. The last two letters can be random 26 letters

Why not Ab or aB or ab?

 

[pka]

Why not Ab or aB or ab?

Abe said in the PO Not case sensitive.

The first two spots must be the letter 'A' followed by 'B' . The letters are next to each other in placement. The last two letters can be random 26 letters

Well that really did not answer my question about repeated letters.
the answer is \(26^2\) if letters can be repeated.
If not then the answer is \(24\cdot 23\).

 

[Harry_the_cat]

Abe said in the PO Not case sensitive.


Well that really did not answer my question about repeated letters.
the answer is \(26^2\) if letters can be repeated.
If not then the answer is \(24\cdot 23\).

Abe asked for the probability, not the number.
If letters can be repeated, there are 26^4 ways of writing 4 letters. 26^2 of them will start with AB. So the probability is ???
If letters can't be repeated there are 26x25x24x23 ways of writing 4 letters. 24x23 of them will start with AB. So the prob is ???

 

[pka]

Abe asked for the probability, not the number.
If letters can be repeated, there are 26^4 ways of writing 4 letters. 26^2 of them will start with AB. So the probability is ???
If letters can't be repeated there are 26x25x24x23 ways of writing 4 letters. 24x23 of them will start with AB. So the prob is ???

Are we now giving out answers?

 

[Deleted member 4993]

Are we now giving out answers?

We waited ~24 hours and the "answers" were not given only a very well-lit path was pointed out.