A tricky question in Eudiometry/Gas analysis

In a eudiometer $$\pu{14 ml}$$ of $$\ce{CH4}$$ and $$\pu{38.5 ml}$$ of $$\ce{O2}$$ was introduced. After explosion and cooling to initial temperature ($$\pu{23°C}$$) the volume of eudiometer was found to be $$\pu{25 ml}$$. Calculate the vapour pressure(in $$\pu{mm Hg}$$) of aqueous solution containing a non-volatile solute (A) at $$\pu{23 °C}$$. Mole fraction of (A) is $$0.1$$. The pressure of eudiometer is $$\pu{1 atm}$$ and is constant.

I wrote the balanced equation. Then applied Avogradro's law and found that the volume of gases in the eudiometer after reaction is $$\pu{24.5ml}$$. So the extra $$\pu{0.5ml}$$ must be due to some water which must have converted into gas. Using $$PV=nRT$$ I can calculate the no. of moles of water evaporated, but I am unable to understand the last part of the question regarding solute A. Is there some information missing in the question regarding solute A? (I assumed it as the final solution after the reaction, but still don't know how to proceed).