(3/4+1/5)×5/19 (12целых1/3-7целых3/4)×6\11
(3/4+1/5)*5/19=(15/20+4/20)*5/19=19/20*5/19=1/4 (12 1/3 - 7 3/4)*6/11=(12 4/12 - 7 9/12)*6/11=(11 16/12 - 7 9/12)*6/11= =4 7/12*6/11=55/12*6/11=5/2=2 1/2