Б) (2 7/15+1 7/12)*11/9-1 7/8= (37/15-19/12)*11/9-15/8= ((148+95)/60)*11/9-15/8= (243*11)/(60*9) - 15/8= (27*11)/60 - 15/8= (9*11)/20 - 15/8= 99/20-15/8= (396-150)/80= 246/80=123/40= 3 3/40
Г) (4 1/3 - 3 4/9)*2+(2 1/4)*2= (13/3-31/9)*2+9/2=((39-31)/9)*2+9/2=8/9 *2+9/2= 16/9+9/2= (32+81)/18=113/18=6 5/18