6.44 Выполните действия: a) $$(8\frac{4}{5}:8 - 6,016 \cdot 0,375 - \frac{2}{35} \cdot 0,07):1\frac{4}{25}$$; б) $$(5\frac{7}{20} - 3,66): 1\frac{6}{7} + (4\frac{5}{8} - 1\frac{1}{4}) : 0,625$$; в) $$(80,6 \cdot 42,2 - 330,52) \cdot (298,53 : 27,9) - 857,56.$$

a) $$(8\frac{4}{5}:8 - 6,016 \cdot 0,375 - \frac{2}{35} \cdot 0,07):1\frac{4}{25}$$; 1. $$8\frac{4}{5} = \frac{44}{5} = 8,8$$ 2. $$8,8:8 = 1,1$$ 3. $$6,016 \cdot 0,375 = 2,256$$ 4. $$\frac{2}{35} \cdot 0,07 = \frac{2}{35} \cdot \frac{7}{100} = \frac{1}{250} = 0,004$$ 5. $$1,1 - 2,256 - 0,004 = -1,16 - 0,004 = -1,16 + (-0,004) = -1,164$$ 6. $$1\frac{4}{25} = \frac{29}{25} = 1,16$$ 7. $$-1,164 : 1,16 = -1,00344827586 \approx -1,0034$$ Ответ: -1,0034 б) $$(5\frac{7}{20} - 3,66): 1\frac{6}{7} + (4\frac{5}{8} - 1\frac{1}{4}) : 0,625$$; 1. $$5\frac{7}{20} = 5 + \frac{7}{20} = 5 + 0,35 = 5,35$$ 2. $$5,35 - 3,66 = 1,69$$ 3. $$1\frac{6}{7} = \frac{13}{7}$$ 4. $$1,69 : \frac{13}{7} = 1,69 \cdot \frac{7}{13} = \frac{1,69 \cdot 7}{13} = \frac{11,83}{13} = 0,91$$ 5. $$4\frac{5}{8} = 4 + \frac{5}{8} = 4 + 0,625 = 4,625$$ 6. $$1\frac{1}{4} = 1 + \frac{1}{4} = 1,25$$ 7. $$4,625 - 1,25 = 3,375$$ 8. $$3,375 : 0,625 = 5,4$$ 9. $$0,91 + 5,4 = 6,31$$ Ответ: 6,31 в) $$(80,6 \cdot 42,2 - 330,52) \cdot (298,53 : 27,9) - 857,56$$ 1. $$80,6 \cdot 42,2 = 3399,32$$ 2. $$3399,32 - 330,52 = 3068,8$$ 3. $$298,53 : 27,9 = 10,7$$ 4. $$3068,8 \cdot 10,7 = 32836,16$$ 5. $$32836,16 - 857,56 = 31978,6$$ Ответ: 31978,6