There is a complex number $z$ with imaginary part $164$ and a positive integer $n$ such that
$$\frac {z}{z + n} = 4i.$$Find $n$.
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There is a complex number $z$ with imaginary part $164$ and a positive integer $n$ such that
$$\frac {z}{z + n} = 4i.$$Find $n$.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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There is a complex number $z$ with imaginary part $164$ and a positive integer $n$ such that
$$\frac {z}{z + n} = 4i.$$Find $n$.
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