1) - 8/5 : (16/25 - 1) - 0,025 : 901 + 1/3 (-6) - 4:2/5= 2) -8 : (-1 1/7) - 1/2 * (-1 1/5) + 6 * (-1/3) - 8:4/5=

Решение:

1) \( -\frac{8}{5} : \left(\frac{16}{25} - 1\right) - 0.025 : 901 + \frac{1}{3} \cdot \left(-6\right) - 4 : \frac{2}{5} \)

1. \(\frac{16}{25} - 1 = \frac{16 - 25}{25} = -\frac{9}{25}\)
2. \(-0.025 = -\frac{25}{1000} = -\frac{1}{40}\)
3. \(-4 : \frac{2}{5} = -4 \cdot \frac{5}{2} = -10\)
4. \(-8/5 : (-9/25) = -8/5 \cdot (-25/9) = 200/45 = 40/9\)
5. \(-1/40 : 901 = -1/(40 \cdot 901) = -1/36040\)
6. \(1/3 \cdot (-6) = -2\)
7. \(40/9 - 1/36040 - 2 - 10 = 40/9 - 1/36040 - 12\)
8. \(40/9 - 12 = (40 - 108)/9 = -68/9\)
9. \(-68/9 - 1/36040 = -(68 \cdot 4004 + 1)/36040 = -(272272 + 1)/36040 = -272273/36040 \approx -7.55\)

2) \( -8 : \left(-1\frac{1}{7}\right) - \frac{1}{2} \cdot \left(-1\frac{1}{5}\right) + 6 \cdot \left(-\frac{1}{3}\right) - 8 : \frac{4}{5} \)

1. \(-1\frac{1}{7} = -8/7\)
2. \(-1\frac{1}{5} = -6/5\)
3. \(-8 : (-8/7) = -8 \cdot (-7/8) = 7\)
4. \(-1/2 \cdot (-6/5) = 6/10 = 3/5\)
5. \(6 \cdot (-1/3) = -2\)
6. \(-8 : 4/5 = -8 \cdot 5/4 = -10\)
7. \(7 + 3/5 - 2 - 10 = 7 + 3/5 - 12\)
8. \(7 - 12 = -5\)
9. \(-5 + 3/5 = (-25 + 3)/5 = -22/5\)

Ответ: 1) \(-272273/36040\); 2) \(-22/5\)