You can 
put this solution on YOUR website! .
Let x be the Joe' salary.  Then
    2x is the Pete' salary
    (x-200)  is the Mark' salary
    x is the Andy' salary
The total salary equation is
    x + 2x + (x-200) + x = 1825.
You do the rest.
Please do not place more than one problem per post.
It is PROHIBITED by the rules of this forum.