200 is the answer i know this because 40%of 200 is 80
solving the equation
we get 
Step-by-step explanation:
Solve the equation:

We can solve using quadratic Formula:

a= 1, b = -12, c = 40
Putting values:

So, solving the equation
we get 
Keywords: Solving quadratic equation
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Answer:
18%
Step-by-step explanation:
=
----> cross multiply
504(100) = 2800x
50400 = 2800x
= 
18 = x
Commission Rate: 18%