Надо 1) 6 1/15 - 5 5/6 + 1 7/12 * 5 1/19 2) 4 1/12 - 3 7/8 + 3 11/18 : 13/18 3) 3 1/7 * 3/11 + 3/8 : 7/12

(1)

6 1/15 - 5 5/6 + 1 7/12 * 5 1/19  = 8 7/30

1) 1 7/12 * 5 1/19 = 19/12 * 96/19 = 8

2) 6 1/15 - 5 5/6 = 6 2/30 - 5 25/30 = 7/30

3) 7/30 + 8 = 8 7/30

ответ: 8 7/30

(2)

4 1/12 - 3 7/8 + 3 11/18 : 13/18  = 5 5/24

1) 3 11/18 : 13/18 = 65/18 * 18/13 = 5

2) 4 1/12 - 3 7/8 = 4 2/24 - 3 21/24 = 5/24

3) 5/24 + 5 = 5 5/24

ответ: 5 5/24

(3)

3 1/7 * 3/11 + 3/8 : 7/12 = 1 1/2

1) 3 1/7 * 3/11 = 22/7 * 3/11 = 6/7

2) 3/8 : 7/12 = 3/8 * 12/7 = 9/14

3) 6/7 + 9/14 = 12/14 + 9/14 = 21/14 = 1 7/14 = 1 1/2

ответ: 1 1/2