# How much amount?

**Classical Mechanics**Level 4

\(100\text{ g}\) of solid \(A\) of specific heat capacity \(50\text{ J/g}^\circ\text{C}\) at \(90^\circ\text{C}\) is placed in a superconducting vessel of mass \(10\text { g}\) of specific heat capacity \(1\text { J/g}^\circ\text{C}\). Then some amount of water at \(40^\circ\text{C}\) is added to the vessel to cool the mixture to \(55^\circ\text{C}\). Now, the above mixture after cooling down obtains a specific heat capacity of \(25\text{ J/g}^\circ\text{C}\). Now, to the above mixture is added a solid \(B\) of specific heat capacity \(20 \text{ J/g}^\circ\text{C}\) at \(10^\circ\text{C}\) such that the final temperature of the overall combination becomes \(30^\circ\text{C}\).

How much amount of solid \(B\) is added (upto 2 decimal places)?