Вычислите: 1)3/8*(-4)+5; 2)5/9: (-1/3)-7; 3)2/5*(-3)-4/5; 4)5/12: 1//3); 5)(1/2)*(-4)-5; 6)4/9: (-2/3)+1.

1) 3/8 · (-4) + 5 = -3/8 · 4/1 + 5 = -3/2 + 5 = -1 целая 1/2 + 5 =

   = 5 - 1 целая 1/2 = 4 целых 2/2 - 1 целую 1/2 = 3 целых 1/2 ;

2) 5/9 : (-1/3) - 7 = -5/9 · 3/1 - 7 = -5/3 - 7 = -1 целая 2/3 - 7 = -(1 целая 2/3 +

    + 7) = -8 целых 2/3 ;

3) 2/5 · (-3) - 4/5 = -2/5 · 3/1 - 4/5 = -6/5 - 4/5 = -(6/5 + 4/5) = - 10/5 = -2 ;

4) 5/12 : 1/4 - (-1/3) = 5/12 · 4/1 + 1/3 = 5/3 + 1/3 = 6/3 = 2;

5) (1/2) · (-4) - 5= -2 - 5 = -(2 + 5) = -7;

6) 4/9 : (-2/3) + 1 = -4/9 · 3/2 + 1 = -2/3 + 1 = 1 - 2/3 = 3/3 - 2/3 = 1/3.