Решение:
$$(14\frac{13}{15}+12\frac{2}{15}) - (11\frac{3}{23}-9\frac{16}{23})=(14+12)+(\frac{13}{15}+\frac{2}{15}) - (11-9+(\frac{3}{23}-\frac{16}{23}))=26+\frac{13+2}{15}-(2+\frac{3-16}{23})=26+\frac{15}{15}-(2+\frac{-13}{23})=26+1-(2-\frac{13}{23})=27-2+\frac{13}{23}=25+\frac{13}{23}=25\frac{13}{23}$$
Ответ: $$25\frac{13}{23}$$