(3 1/4+2 1/6):2 3/5-2/3:4/9
(3 1/4+2 1/6):2 3/5-2/3:4/9=(3 3/12+2 2/12):2 3/5-2/3*9/4= =5 5/12:2 3/5-2/1*3/4=65/12:13/5-1/1*3/2=65/12*5/13-1/1*3/2= =5/12*5/1-3/2=25/12-3/2=25/12-18/12=7/12
спасибо