X_(NaCl)=0.0927
X_(NaCl) + X_(H_2O) = 1
X_(H_2O) = 1 - X_(NaCl)
X_(H_2O) = 1 - 0.0927
X_(H_2O) = 0.9073
X_(NaCl) /X_(H_2O) = 0.0927/0.9073=0.1022
X_(NaCl) / X_(H_2O)=( n_(NaCl)/(n_(NaCl) +n_(H_2O)))/( n_(H_2O)/(n_(NaCl) +n_(H_2O)))=( n_(NaCl)/cancel((n_(NaCl) +n_(H_2O))))/( n_(H_2O)/cancel((n_(NaCl) +n_(H_2O))))=n_(NaCl)/n_(H_2O)
n_(NaCl)/n_(H_2O)=0.1022
%\ by \ mass= m_(NaCl)/((m_(NaCl)+m_(H_2O)))xx100
mass= nxxMM
"Where "MM" is the molar mass and "n" is the number of moles."
%\ by \ mass=((n_(NaCl)xxMM_(NaCl)))/((n_(NaCl)xxMM_(NaCl)+n_(H_2O)xxMM_(H_2O)))xx100
"Divide both, numerator and denominator by " n_(H_2O)
%\ by \ mass=(((n_(NaCl)xxMM_(NaCl))/n_(H_2O)))/ (((n_(NaCl)xxMM_(NaCl)+n_(H_2O)xxMM_(H_2O))/n_(H_2O)))xx100
%\ by \ mass=((n_(NaCl)/n_(H_2O)xxMM_(NaCl)))/ ((n_(NaCl)/n_(H_2O)xxMM_(NaCl)+n_(H_2O)/n_(H_2O)xxMM_(H_2O)))xx100
%\ by \ mass=((n_(NaCl)/n_(H_2O)xxMM_(NaCl)))/ ((n_(NaCl)/n_(H_2O)xxMM_(NaCl)+cancel(n_(H_2O))/cancel(n_(H_2O))xxMM_(H_2O)))xx100
%\ by \ mass=((n_(NaCl)/n_(H_2O)xxMM_(NaCl)))/ ((n_(NaCl)/n_(H_2O)xxMM_(NaCl)+MM_(H_2O)))xx100
%\ by \ mass=(0.1022xx58.45 \ g*mol^-1)/ (0.1022xx58.45\ g*mol^1+18.016\ g.mol^-1)xx100
%\ by \ mass= 24.9\ %