1. а)11/48+13/48+17/48; б) 19/55+18/55+12/55; в) 25/64+17/64+15/64; г) 23/69+38/69+7/69; д) 28/43+52/43+19/43; е) 17/45+11/45+23/45. 2. а) 1/5+3/4+1/5+1/4; б) 11/12+7/10+3/100+1/12; в) 12/17+15/24+3/8+5/17; г) 3/7+5/9+4/9+4/7. , . с объяснением ฅ'ω'ฅ

(25/64+15/64)+17/64= 40/64+17/64=57/64
(13/48+17/48)+11/48=30/48+11/48=41/48
19/55+(18/55+12/55)=19/55+30/55=49/55
23/69+7/69)+38/69=30/69+38/69=68/39
(28/43+52/43)+19/43= 80/43+19/43=99/43
(17/45+23/45)+11/45=40/45+11/45=51/45