The equations of both the sister are the same.
<h2>Expression </h2>In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations that are formed according to rules which are dependent on the context.
<h2>Given to us</h2>Gabriel Equation: ,
Gabriel's Sister Equation: ,
On further solving the equation we get,
As we can see the equation transformed to Gabriel's Equation of total cost.
Therefore, both the sisters are correct as the equations of both the sister are the same.
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