Решение:
а) \( (0,411 - 1\frac{3}{8} - 1\frac{3}{4}) : 0,59 \)
- \( 1\frac{3}{8} = \frac{11}{8} = 1,375 \)
- \( 1\frac{3}{4} = \frac{7}{4} = 1,75 \)
- \( 0,411 - 1,375 - 1,75 = 0,411 - 3,125 = -2,714 \)
- \( -2,714 : 0,59 = -4,6 \)
б) \( (1,35 - 6\frac{8}{15}) : (2\frac{1}{5} + 0,2) \)
- \( 6\frac{8}{15} = \frac{98}{15} \approx 6,533 \)
- \( 1,35 - \frac{98}{15} = \frac{135}{100} - \frac{98}{15} = \frac{27}{20} - \frac{98}{15} = \frac{81 - 392}{60} = -\frac{311}{60} \approx -5,183 \)
- \( 2\frac{1}{5} = \frac{11}{5} = 2,2 \)
- \( 2,2 + 0,2 = 2,4 \)
- \( -\frac{311}{60} : 2,4 = -\frac{311}{60} : \frac{24}{10} = -\frac{311}{60} \times \frac{10}{24} = -\frac{311}{144} \approx -2,1597 \)
в) \( 12,8 \cdot 0,25 : (0,125 - \frac{3}{4}) \)
- \( 12,8 \cdot 0,25 = 3,2 \)
- \( 0,125 = \frac{1}{8} \)
- \( \frac{1}{8} - \frac{3}{4} = \frac{1 - 6}{8} = -\frac{5}{8} = -0,625 \)
- \( 3,2 : (-0,625) = -5,12 \)
г) \( \frac{1,5 + 2\frac{2}{3} + 3\frac{3}{4}}{15\frac{1}{8} : 2 - 14} \)
- Числитель:
- \( 1,5 = \frac{3}{2} \)
- \( 2\frac{2}{3} = \frac{8}{3} \)
- \( 3\frac{3}{4} = \frac{15}{4} \)
- \( \frac{3}{2} + \frac{8}{3} + \frac{15}{4} = \frac{18 + 32 + 45}{12} = \frac{95}{12} \approx 7,9167 \)
- Знаменатель:
- \( 15\frac{1}{8} = \frac{121}{8} \)
- \( \frac{121}{8} : 2 = \frac{121}{16} \approx 7,5625 \)
- \( \frac{121}{16} - 14 = \frac{121 - 224}{16} = -\frac{103}{16} \approx -6,4375 \)
- Итого:
- \( \frac{95}{12} : (-\frac{103}{16}) = \frac{95}{12} \times (-\frac{16}{103}) = -\frac{95 \times 4}{3 \times 103} = -\frac{380}{309} \approx -1,2298 \)
д) \( (2,7 + 1\frac{1}{3} - 1\frac{4}{5}) \cdot \frac{53}{67} \)
- \( 1\frac{1}{3} = \frac{4}{3} \approx 1,333 \)
- \( 1\frac{4}{5} = \frac{9}{5} = 1,8 \)
- \( 2,7 + \frac{4}{3} - 1,8 = 0,9 + \frac{4}{3} = \frac{9}{10} + \frac{4}{3} = \frac{27 + 40}{30} = \frac{67}{30} \approx 2,233 \)
- \( \frac{67}{30} \cdot \frac{53}{67} = \frac{53}{30} \approx 1,7667 \)
е) \( 1\frac{1}{16} : (7\frac{2}{5} - 12\frac{3}{8} + 37,525) \)
- \( 1\frac{1}{16} = \frac{17}{16} \)
- \( 7\frac{2}{5} = \frac{37}{5} = 7,4 \)
- \( 12\frac{3}{8} = \frac{99}{8} = 12,375 \)
- \( 7,4 - 12,375 + 37,525 = -4,975 + 37,525 = 32,55 \)
- \( \frac{17}{16} : 32,55 = \frac{17}{16} : \frac{3255}{1000} = \frac{17}{16} \times \frac{1000}{3255} = \frac{17 \times 125}{2 \times 3255} = \frac{2125}{6510} = \frac{425}{1302} \approx 0,3264 \)
ж) \( (\frac{3}{7} + 0,7 - \frac{1}{10}) \cdot 5\frac{5}{6} \)
- \( 0,7 = \frac{7}{10} \)
- \( \frac{3}{7} + \frac{7}{10} - \frac{1}{10} = \frac{3}{7} + \frac{6}{10} = \frac{3}{7} + \frac{3}{5} = \frac{15 + 21}{35} = \frac{36}{35} \)
- \( 5\frac{5}{6} = \frac{35}{6} \)
- \( \frac{36}{35} \cdot \frac{35}{6} = \frac{36}{6} = 6 \)
3) \( \frac{\frac{1}{25} + 12\frac{3}{5} - 8,9}{0,2388 : 796} \cdot 0,5 \)
- Числитель:
- \( 12\frac{3}{5} = 12,6 \)
- \( \frac{1}{25} = 0,04 \)
- \( 0,04 + 12,6 - 8,9 = 12,64 - 8,9 = 3,74 \)
- Знаменатель:
- \( 0,2388 : 796 = 0,0003 \)
- Итого:
- \( \frac{3,74}{0,0003} \cdot 0,5 = \frac{37400}{3} \cdot 0,5 = \frac{18700}{3} \approx 6233,33 \)
Ответ: а) -4,6; б) ≈ -2,16; в) -5,12; г) ≈ -1,23; д) ≈ 1,77; е) ≈ 0,33; ж) 6; 3) ≈ 6233,33.