помогите решить примеры: 1 6/7+3/7, 9 5/12-3 1/6, 2 1/3:5 4/9, 3/5*7/9*15/14

1 6/7+3/7=1 9/7=2 2/7

9 5/12-3 1/6=9 5/12-3 2/12=6 3/12

2 1/3 : 5 4/9=7/3:49/9=7/3*9/49=63/147=9/21=3/7

3/5*7/9*15*14=3*7*15/5*9*14=315/630=1/2

1)1 6/7 + 3/7 = 13/7 + 3/7 = 17/7 = 2 2/72)9 5/12 - 3 1/6 = 3 5/4 - 1/2 = 15/4 - 1/2 = 13/4 = 3 1/4 = 3,253)2 1/3 : 5 4/9 = 7/3 : 49/ 9 = 3/74) 3/5 * 7/9 * 15/14 = 3/6 = 1/2 = 0,5