What is the capacity of a fire reservoir, in thousands of cubic meters of water, which is currently filled up to three quarters of its capacity?
1. If $${3}*{10}^{3}$$ thousand cubic meters of water were pumped into the reservoir, it would be filled to $$\frac{7}{8}$$ of its capacity.
2. If $${6}*{10}^{3}$$ thousand cubic meters of water were removed from the reservoir, if would be filled to $$\frac{1}{2}$$ of its capacity.