7,8*2,7/9*0,3*3,9= 6*1,3*9*0,3/9*0,3*1,3*3=
=6/3=2;
2) 8а+16а/2*8а=24a/16a=3/2=1,5;
3) 31*90-35*31/35*31=31*(90-35)/31*35=
=55/35=5*11/5*7=11/7=1 4/7;
4) 57х+19х/19х*4=3*19x+19x/19x*4=4*19x/19x*4=1
7,8*2,7/9*0,3*3,9= 6*1,3*9*0,3/9*0,3*1,3*3=
=6/3=2;
2) 8а+16а/2*8а=24a/16a=3/2=1,5;
3) 31*90-35*31/35*31=31*(90-35)/31*35=
=55/35=5*11/5*7=11/7=1 4/7;
4) 57х+19х/19х*4=3*19x+19x/19x*4=4*19x/19x*4=1