Resposta :
Explicação passo-a-passo:
111)a)2/3+1/2-7/4=
8+6-21/12
-7/12
2) a)(+2/6):(-5/4)
2.4/4.5
-4/5
b)(-18/17)×(+34/27)=
18.34/17.27
68/51
Explicação passo-a-passo:
111)a)2/3+1/2-7/4=
8+6-21/12
-7/12
2) a)(+2/6):(-5/4)
2.4/4.5
-4/5
b)(-18/17)×(+34/27)=
18.34/17.27
68/51