The fourth degree polynomial equation $x^4 - 7x^3 + 4x^2 + 7x - 4 = 0$ has four real roots, $a$, $b$, $c$ and $d$. What is the value of the sum $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}+\frac{1}{d}$? Express your answer as a common fraction.
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<|im_start|>user
The fourth degree polynomial equation $x^4 - 7x^3 + 4x^2 + 7x - 4 = 0$ has four real roots, $a$, $b$, $c$ and $d$. What is the value of the sum $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}+\frac{1}{d}$? Express your answer as a common fraction.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
\frac{7}{4}
The fourth degree polynomial equation $x^4 - 7x^3 + 4x^2 + 7x - 4 = 0$ has four real roots, $a$, $b$, $c$ and $d$. What is the value of the sum $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}+\frac{1}{d}$? Express your answer as a common fraction.
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