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### Finding solution of expression with fractional power

I'm trying to solve this equation

$3(2.2+(\frac{64}{r})^{(1/3)})= 4(2.2+(\frac{128}{r-1})^{(1/4)})$ using solve function

I want to obtain the numerical solution

but when i use sol[0].n(30)

TypeError: cannot evaluate symbolic expression numerically

when i try to find_root(0,1,r)

ValueError: negative number to a fractional power not real

How to find the solution of this expression ?