I am trying to solve [this equation](http://imgur.com/x0B7cNn)

The link has a screen capture of the equation and the solution. I am looking for the values of a1 and a2 in particular, but they need to be real numbers. s1 and s2 are integers. Now if I remove the condition of integers, then (as expected) the computation takes too long (it hadn't finished for an hour). My questions are:

1. Is it possible to define a1 and a2 to be reals, and s1 and s2 to be integers? 

2. I would like to reduce the possible values of a1 and a2 to the tenth decimal point (i.e. between 0 and 1, it can have 0.1, 0.2, 0.3,...0.9). Can this be done in *Mathematica*?

Edit (The code for the equation): 

    Maximize[{3/100000 - (
       Subscript[s, 1]*Subscript[a, 1] + 
        Subscript[s, 2]*Subscript[a, 2])/(50000 Subscript[a, 1]) - (
       3 (Subscript[s, 1]*Subscript[a, 1] + 
          Subscript[s, 2]*Subscript[a, 2]))/(25000 Subscript[a, 2]) + 1/(
       400000000000 Subscript[a, 1] Subscript[a, 2]) + (
       3 (Subscript[s, 1]*Subscript[a, 1] + 
          Subscript[s, 2]*Subscript[a, 2])^2)/(
       100000 Subscript[a, 1] Subscript[a, 2]) + (9 Subscript[a, 1])/(
       100000 Subscript[a, 2]), 
      Subscript[a, 1] >= 1 && Subscript[a, 1] <= 5 && 
       Subscript[a, 2] >= 1 && Subscript[a, 2] <= 5 && 
       Subscript[s, 1] + Subscript[s, 2] == 10 && Subscript[s, 1] >= 0 && 
       Subscript[s, 2] >= 0}, {Subscript[a, 1], Subscript[a, 2], 
      Subscript[s, 1], Subscript[s, 2]}, Integers]