1) 3/8 * (-4) + 5=

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

3) 2/5 * (-3) - 4/5=

4) 5/12:1/4 - (-1/3) =

5) (1/2) * (-4) - 5=

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

1) 3/8 * (-4) + 5=

Сокращаем 8 и 4 на 4

3/2• (-1) + 5 = - 3/2 + 5 = 5 - 3/2=

4 2/2 - 1 1/2 = 3 1/2 = 3,5

2) 5/9: (-1/3) - 7 = 5/9• (-3/1) - 7=

Сокращаем 9 и 3 на 3

5/3• (-1/1) - 7 = - 5/3 - 7 = - (7 + 5/3) =

- (7 + 1 2/3) = - 8 2/3

3) 2/5 * (-3) - 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=

Сокращаем 12 и 4 на 4;

5/3• 1/1 + 1/3=

5/3+1/3 = 6/3 = 2.

5) (1/2) * (-4) - 5=Сокращаем 2 и 4 на 2

1/1• (-2) - 5 = - 2-5 = - (2+5) = - 7

6) 4/9: (-2/3) + 1 = 4/9• (-3/2) + 1=

Сокращаем 9 и 3 на 3; 4 и 2 на 2

2/3• (-1/1) + 1 = - 2/3+1 = 1 - 2/3=

3/3 - 2/3 = 1/3