Solution - Simplification or other simple results

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "0.000000081" was replaced by "(000000081/1000000000)".

Step  1  :

                81    
 Simplify   ——————————
            1000000000

Equation at the end of step  1  :

      81    
  —————————— • a
  1000000000

Step  2  :

Final result :

      81a   
  ——————————
  1000000000