Solution - Simplification or other simple results

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "^-3" was replaced by "^(-3)".

(2): "4.2" was replaced by "(42/10)".

Step  1  :

 1.1     10 = 2•5

(10)^-3 = (2•5)^(-3) = (2)^(-3) • (5)^(-3)

Equation at the end of step  1  :

  42
  —— • ((2)(-3)•(5)(-3))
  10

Step  2  :

            21
 Simplify   ——
            5 

Equation at the end of step  2  :

  21
  —— • ((2)(-3)•(5)(-3))
  5 

Step  3  :

Multiplying exponents :

 3.1    5¹  multiplied by  5³   = 5^{(1 + 3)} = 5⁴

Final result :

   21            
  ———— = 0.00420 
  5000