How many permutations for a 7 characters in length string, which contains all following letters R, X, S, Y, T, Z, U, has either the string 'RXS' or string 'ZU' in the 7 characters string?

Following are the solution to this question:

Explanation:

In the following forms, RXS can appear:  

it may look like that really, forms = 24 may construct the remainder of its letters.  

it may look like that really,   forms = 24 may construct the remainder of its letters.  

it may look like that really, forms = 24 may construct the remainder of its letters.  

it may look like that really,   forms = 24 may construct the remainder of its letters.  

it may look like that really,   forms = 24 may construct the remainder of its letters.  

And we'll have a total of permutations with both the string RXS.

In the following forms, UZ can appear:

 They can organize your remaining 5 characters through 5 categories! Procedures

They can organize your remaining 5 characters through 5 categories! Procedures

They can organize your remaining 5 characters through 5 categories! Procedures  

They can organize your remaining 5 characters through 5 categories! Procedures  

They can organize your remaining 5 characters through 5 categories! Procedures  

They can organize your remaining 5 characters through 5 categories! Procedures  

There may be ways of complete permutations.

the answer is e ; )(: