5. Вычислите значение дробного выражения: 1) ((2,25 + 3 2/3) · 1,2)/(8,5 − 2/5); 2) (1 9/16 · 3,2 + 2/3 − 9 : 2,4)/(17 7/12 − 6 1/3).

1. \[\frac{\left(2.25+3\frac23\right)\cdot1.2}{8.5-\frac25}=\frac{\left(\frac94+\frac{11}{3}\right)\cdot\frac65}{\frac{81}{10}-\frac4{10}}=\frac{\frac{71}{12}\cdot\frac65}{\frac{77}{10}}=\frac{71}{77}.\]
2. \[\frac{1\frac9{16}\cdot3.2+\frac23-9:2.4}{17\frac7{12}-6\frac13}=\frac{\frac{25}{16}\cdot\frac{16}{5}+\frac23-\frac{15}{4}}{\frac{211}{12}-\frac{19}{3}}=\frac{5+\frac23-\frac{15}{4}}{\frac{45}{4}}=\frac{\frac{23}{12}}{\frac{45}{4}}=\frac{23}{135}.\]

Ответ: 1) \(\frac{71}{77}\); 2) \(\frac{23}{135}\).