A total fixed amount of $N$ thousand rupees is given to $A$, $B$, and $C$ every year, each receiving an amount proportional to their age. In the first year, $A$ received half of the total amount. When the sixth payment was made, $A$ received six-sevenths of the amount she received in the first year; $B$ received 1000 Rs less than she received in the first year, and $C$ received twice the amount she received in the first year. Find $N$.

Let's think step by step and output the final answer within \boxed{}.
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