Question

Помогите пожалуйста по математике

Answer 1

1)(7,8*2,7)/(9*0,3*3,9)=(7,8*2,7)/(2,7*3,9)=3,9*2/3,9=2

2)(8а+16а)/(2*8а)=(8а*(1+2))/(2*8а)=3/2

3)(31*90-35*31)/31*35=(31*(90-35))/(31*35)=55/35=1  20/35 = 1  4/7

4)(57х+19х)/(19х*4)=(19х(3+1))/(19х*4)=1