(3 1/15-1 1/15:1 3/5+2/5)*2 1/7-1 1/7=
1) 1 1/15 : 1 3/5 = 16/15 * 5/8 = 2/3 2) 3 1/15 - 2/3 = 2 16/15 - 10/15 = 2 6/15 = 2 2/5 3) 2 2/5 + 2/5 = 2 4/5 4) 2 4/5 * 2 1/7 = 14/5 * 15/7 = 6 5) 6 - 1 1/7 = 5 7/7 - 1 1/7 = 4 6/7