$\frac{(\frac{23}{36} + \frac{31}{63} - (\frac{3}{4} + \frac{5}{21})) * (48 : (\frac{3}{5} : \frac{7}{8}))}{(\frac{19}{26} + \frac{14}{39} - \frac{1}{6}) * (54\frac{1}{6} : (8\frac{4}{7} : \frac{12}{35}))} = \frac{(\frac{23 * 7 + 31 * 4}{252} - \frac{3 * 21 + 5 * 4}{84}) * (48 : (\frac{3}{5} * \frac{8}{7}))}{\frac{19 * 3 + 14 * 2 - 1 * 13}{78} * (\frac{325}{6} : (\frac{60}{7} * \frac{35}{12}))} = \frac{(\frac{161 + 124}{252} - \frac{63 + 20}{84}) * (48 : \frac{24}{35})}{\frac{57 + 28 - 13}{78} * (\frac{325}{6} : (\frac{12 * 5}{7} * \frac{5 * 7}{12}))} = \frac{(\frac{285}{252} - \frac{83}{84}) * (\frac{24 * 2}{1} * \frac{35}{24})}{\frac{72}{78} * (\frac{326}{6} : 25)} = \frac{\frac{285 - 83 * 3}{252} * (2 * 35)}{\frac{12 * 6}{13 * 6} * (\frac{325}{6} : 25)} = \frac{\frac{285 - 249}{252} * 70}{\frac{12}{13} * (\frac{13 * 25}{6} * \frac{1}{25})} = \frac{\frac{36}{36 * 7} * 7 * 10}{\frac{12}{13} * \frac{13}{6}} = \frac{10}{2} = 5$