Question 368949
{{{(10x^2y)^3 / (25x^2y^3)^4}}}
= {{{1000x^6y^3/390625x^8y^12}}}
= {{{8/3125x^2y^9}}}
or
{{{2.56*x^-2*y^-9*10^-3}}}
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"Simplest" is not a well defined term.