3-(3\7- 12\35 ) :6\7 = 2 14/15
1) 3/7 - 13/35 = 15/35 - 13/35 = 2/35
2) 2/35 : 6/7 = 2/35 : 30/35 = 1/15
3) 3 - 1/15 = 2 15/15 - 1/15 = 2 14/15
1\2 -3\4 * (7\15-3\10) = 3/8
1) 7/15 - 3/10 = 14/30 - 9/30 = 5/30 = 1/6
2) 3/4 * 1/6 = 9/12 * 2/12 = 9/72 = 1/8
3) 1/2 - 1/8 = 4/8 - 1/8 = 3/8