Увеличьте число 5 : а) в 4 раза; б) на 4; в) в 7 раз ; г) на 7. .

(25 - 8 3/4) + (13 5/12 - 2 11/18) - (2 2/9 - 1 3/4) = 9 7/12

1) 25 - 8 3/4 = 24 4/4 - 8 3/4 = 16 1/4

2) 13 5/12 - 2 11/18 = 13 15/36 - 2 22/36 = 12 51/36 - 2 22/36 = 10 29/36

3) 2 2/9 - 1 3/4 = 2 8/36 - 1 27/36 = 1 44/36 - 1 27/36 = 17/36

4) 16 1/4 + 10 29/36 = 16 9/36 + 10 29/36 = 26 38/36 = 27 2/36

5) 27 2/36 - 17/36 = 26 38/36 - 17/36 = 9 21/36 = 9 7/12 

12 7/10 - 3 1/2 - (4 1/2 - 3 3/4) = 8 9/20

1) 4 1/2 - 3 3/4 = 4 2/4 - 3 3/4 = 3 6/4 - 3 3/4 = 3/4

2) 12 7/10 - 3 1/2 = 12 7/10 - 3 5/10 = 9 2/10

3) 9 2/10 - 3/4 = 9 4/20 - 15/20 = 8 24/20 - 15/20 = 8 9/20