Вычисли значения выражений в заданиях 10-14 под буквами a и b

10. a) \( \frac{1}{2} + \frac{1}{3} + \frac{1}{5} = \frac{15}{30} + \frac{10}{30} + \frac{6}{30} = \frac{15+10+6}{30} = \frac{31}{30} = 1 \frac{1}{30} \) б) \( \frac{1}{3} + \frac{3}{4} + \frac{5}{12} = \frac{4}{12} + \frac{9}{12} + \frac{5}{12} = \frac{4+9+5}{12} = \frac{18}{12} = \frac{3}{2} = 1 \frac{1}{2} \) в) \( \frac{3}{5} + \frac{5}{6} + \frac{1}{2} = \frac{18}{30} + \frac{25}{30} + \frac{15}{30} = \frac{18+25+15}{30} = \frac{58}{30} = \frac{29}{15} = 1 \frac{14}{15} \) 11. a) \( \frac{1}{3} - \frac{1}{5} - \frac{1}{15} = \frac{5}{15} - \frac{3}{15} - \frac{1}{15} = \frac{5-3-1}{15} = \frac{1}{15} \) б) \( \frac{1}{2} - \frac{2}{5} - \frac{1}{10} = \frac{5}{10} - \frac{4}{10} - \frac{1}{10} = \frac{5-4-1}{10} = \frac{0}{10} = 0 \) в) \( \frac{7}{8} - \frac{1}{4} - \frac{1}{2} = \frac{7}{8} - \frac{2}{8} - \frac{4}{8} = \frac{7-2-4}{8} = \frac{1}{8} \) 12. a) \( 3 \frac{1}{3} + 2 \frac{1}{6} = 3 + \frac{1}{3} + 2 + \frac{1}{6} = 5 + \frac{2}{6} + \frac{1}{6} = 5 + \frac{3}{6} = 5 + \frac{1}{2} = 5 \frac{1}{2} \) б) \( \frac{3}{5} + 4 \frac{1}{2} = \frac{3}{5} + 4 + \frac{1}{2} = 4 + \frac{6}{10} + \frac{5}{10} = 4 + \frac{11}{10} = 4 + 1 \frac{1}{10} = 5 \frac{1}{10} \) в) \( 1 \frac{3}{7} + 2 \frac{1}{2} = 1 + \frac{3}{7} + 2 + \frac{1}{2} = 3 + \frac{6}{14} + \frac{7}{14} = 3 + \frac{13}{14} = 3 \frac{13}{14} \) 13. a) \( 1 \frac{1}{8} - \frac{3}{4} = 1 + \frac{1}{8} - \frac{3}{4} = 1 + \frac{1}{8} - \frac{6}{8} = 1 - \frac{5}{8} = \frac{8}{8} - \frac{5}{8} = \frac{3}{8} \) б) \( 1 \frac{3}{5} - \frac{2}{3} = 1 + \frac{3}{5} - \frac{2}{3} = 1 + \frac{9}{15} - \frac{10}{15} = 1 - \frac{1}{15} = \frac{15}{15} - \frac{1}{15} = \frac{14}{15} \) в) \( 2 \frac{1}{6} - 1 \frac{3}{4} = 2 + \frac{1}{6} - 1 - \frac{3}{4} = 1 + \frac{2}{12} - \frac{9}{12} = 1 - \frac{7}{12} = \frac{12}{12} - \frac{7}{12} = \frac{5}{12} \) 14. a) \( \frac{1}{2} + x = \frac{3}{4} \) \( x = \frac{3}{4} - \frac{1}{2} \) \( x = \frac{3}{4} - \frac{2}{4} \) \( x = \frac{1}{4} \) в) \( \frac{3}{5} + x = \frac{3}{4} \) \( x = \frac{3}{4} - \frac{3}{5} \) \( x = \frac{15}{20} - \frac{12}{20} \) \( x = \frac{3}{20} \)