Expected value in a circle

[Bootsif]

hey would like to know the solution for the following problem.
Four boys and six girls are randomly sitting in a circle, what is the expected value of the number of girls so that from their right and left there's a boy ?
final answer is 1.

 

[pka]

Four children and six girls are randomly sitting in a circle, what is the expected value of the number of girls so that from their right and left there's a boy ? final answer is 1.

Is this a translation into English? It certainly is a jumble of English. The phrase "four children and six girls" could mean there are ten young people who may all be females or six girls & four boys. There is really no definite way to read this.
So please review the post and correct it by giving a clear description of the group sex-wise.

 

[Dr.Peterson]

hey would like to know the solution for the following problem.
Four children and six girls are randomly sitting in a circle, what is the expected value of the number of girls so that from their right and left there's a boy ?
final answer is 1.

Here's a possible corrected version of the problem:

Ten children, six of whom are girls, are randomly sitting in a circle. What is the expected number of girls who are sitting between two boys (that is, they have a boy immediately on each side)?​

Now it's your turn again: Please do as we ask and show what ideas you have, so we can tell what help you need, and what we don't have to tell you because you already know it. While you do that, I'll give the problem a try, so I can see whether the answer to my version is 1.

 

[Bootsif]

Is this a translation into English? It certainly is a jumble of English. The phrase "four children and six girls" could mean there are ten young people who may all be females or six girls & four boys. There is really no definite way to read this.
So please review the post and correct it by giving a clear description of the group sex-wise.

Here's a possible corrected version of the problem:

Four children, six of whom are girls, are randomly sitting in a circle. What is the expected number of girls who are sitting between two boys (that is, they have a boy immediately on each side)?​

Now it's your turn again: Please do as we ask and show what ideas you have, so we can tell what help you need, and what we don't have to tell you because you already know it. While you do that, I'll give the problem a try, so I can see whether the answer to my version is 1.

sorry. typo. I meant four boys and six girls.

And I dont have a clue about how to solve it.. I've tried using indicator which count girls that fulfiil the demand and to sum it.

 

[Dr.Peterson]

It appears from some of the other questions you've submitted that you have learned some relatively advanced methods. It might help if you told us what topic the problem appears to be intended to give you practice with.

But if you calculate the total number of possible arrangements, you'll see that it is entirely feasible just to list them all and count. Have you tried that?

In any case, please show actual work rather than just describe it, because that gives us a lot more to work with. You might be doing something right but made a little mistake, or we might see that you are misinterpreting the problem, or whatever.