1)1200*3/8=450г надо валерианы
2)1200*1/8=150г надо пустырника
3/4 * (8/15 -1/6)=3/4*(16/30-5/30)=3/4*11/30=33/120=11/40
2/5 * (10 /11 + 15/16)=2/5*(160/176+165/176)=2/5*325/176=650/880=65/88
1/2 *(0,5-2+ 46)=1/2*24=12
3/4*(0,75+ 8/13 - 8/9)=9/16+6/13-2/3=223/624