11-(3- 1 4/15) : 4/25 + 8/15 решение много .

11-(3- 1 4/15) : 4/25 + 8/15 = 7/10,

1) 3 - 1 4/15 = 2 15/15 - 1 4/15 = 1 11/15,
2) 1 11/15 : 4/25 = 26/15 * 25/4 = 65/6 = 10 5/6,
3) 11 - 10 5/6 = 10 6/6 - 10 5/6 = 1/6,
4) 1/6 + 8/15 = 5/30 + 16/30 = 21/30 = 7/10