1,2/4-4/7 помогите пож
1.2 =1 2/10 =1 1/5= 6/5 6/5 :4 -4/7 =6/5 *1/4 -4/7 = 6/20 -4/7 =3/10 -4/7 = (21-40)/70= -19/70