а) (23,437+7,9)-(1,41-0,53)=30,457
1)23,437+7,9=31,337
2)1,41-0,53=0,88
3)31,337-0,88=30,457
б) 55,28+6,438-(8,6+0,738)=52,38
1)8,6+0,738=9,338
2)55,28+6,438=61.718
3)61,718-9,338=52,38
в) 50-(4,123+5,68+31,7)=8,487
1)4,123+5,68=9,803
2)9,803+31,7=41.503
3)50-41,503=8,487
г) 100,6-(47,84+26,3)-9,208=17,252
1)47,84+26,3=74,14
2)100,6-74,14=26,46
3)26,46-9,208=17,252