Let the charge on each capacitor be \\\\(q\\\\)thus the potential against each capacitor will be\\\\((q\\\\) is in micro coulomb\\\\()\\\\)across \\\\(C_1\\\\) capacitor \\\\(= q/20V\\\\)across \\\\(C_2\\\\) capacitor \\\\(= q/40V\\\\)across \\\\(C_3\\\\) capacitor \\\\(= q/50V\\\\)as we can see for same charge on each capacitor as they connected in series, the capacitor \\\\(C_1\\\\)has maximum potential drop, which according to the situation can be \\\\(50V\\\\)so \\\\(q/20=50\\\\)so \\\\(q= 1000\\\\) micro coulombso the potential drop against \\\\(C_2\\\\) capacitor \\\\(= 1000/40 = 25\\\\) voltswhile the potential drop against \\\\(C_3\\\\) capacitor will be \\\\(1000/50 = 20\\\\) voltshence as all the capacitors are in series so the potential difference across \\\\(X\\\\) and \\\\(Y\\\\) \\\\(=50 + 25 + 20 = 95\\\\) volts