1. а) 5/6 − 11/24; б) 3/4 + 2 7/30; в) 3 5/28 − 1 2/21; г) 8 4/7 · 4 1/5; д) 2 2/5 : 1 1/15.

1. \(\frac56-\frac{11}{24}=\frac{20}{24}-\frac{11}{24}=\frac38\).
2. \(\frac34+2\frac7{30}=\frac34+\frac{67}{30}=\frac{45+134}{60}=\frac{179}{60}=2\frac{59}{60}\).
3. \(3\frac5{28}-1\frac2{21}=\frac{89}{28}-\frac{23}{21}=\frac{267-92}{84}=\frac{175}{84}=2\frac1{12}\).
4. \(8\frac47\cdot4\frac15=\frac{60}{7}\cdot\frac{21}{5}=36\).
5. \(2\frac25:1\frac1{15}=\frac{12}{5}:\frac{16}{15}=\frac{12}{5}\cdot\frac{15}{16}=\frac94=2\frac14\).

Ответ: а) \(\frac38\); б) \(2\frac{59}{60}\); в) \(2\frac1{12}\); г) 36; д) \(2\frac14\).