1) (1/2+1/3)*(1/5 - 1/4) 3) (0,3- 1/20): (3/4 - 1,25)

2) (2/7-3/4)*(2/13 - 1/2) 4) (2,7 - 1/5) : (1/2 +4,5)

!

1) -1/24

2) 9/56

3) -1/2 или -0,5

4) -5/8 или -0,6

Объяснение:

1) (1/2+1/3)×(1/5-1/4)

5/6×(-1/20)

-1/6×1/4= -1/24

2) (2/7-3/4)×(2/13-1/2).

-13/28×(-9/26)

1/28×9/2=9/56

3)(0,3-1/20):(3/4-1,25)

(3/10-1/20):(3/4-5/4)

1/4:(-1/2)

-1/4×2= -1/2= -0,5

4) (2,7-1/5):(1/2+4,5)

(27/10-1/5):(1/2-9/2)

5/2:(-4)

-5/2×1/4=-5/8 =-0,6