12. Вычислите: A) \(\frac{1}{2} + \frac{1}{4} + \frac{1}{8}\) Б) \(\frac{1}{2} + \frac{1}{3} + \frac{1}{6}\) B) \(\frac{1}{3} + \frac{1}{4} + \frac{1}{2}\) Г) \(\frac{1}{3} + \frac{1}{4} + \frac{1}{12}\) Д) \(\frac{1}{3} + \frac{1}{5} + \frac{1}{15}\) E) \(\frac{1}{2} + \frac{3}{7} + \frac{5}{14}\) E) \(\frac{1}{4} + \frac{3}{5} + \frac{7}{7}\) Ж) \(\frac{1}{4} + \frac{1}{3} + \frac{1}{5}\) 3) \(\frac{2}{3} + \frac{1}{2} + \frac{3}{7}\) И) \(\frac{3}{4} + \frac{11}{12} + \frac{4}{5}\) K) \(\frac{7}{8} + \frac{14}{15} + \frac{15}{16}\) Л) \(4\frac{15}{49} - 2\frac{3}{14}\) M) \(5\frac{7}{12} - 2\frac{2}{15}\) O) \(\frac{11}{14} - \frac{3}{7}\) И) \(\frac{3}{5} + \frac{3}{1} + \frac{1}{7}\) P) \(3\frac{13}{44} - 1\frac{7}{33}\) T) \(2\frac{5}{5} - 1\frac{6}{7}\)

12. Вычислите:

A) \( \frac{1}{2} + \frac{1}{4} + \frac{1}{8} = \frac{4}{8} + \frac{2}{8} + \frac{1}{8} = \frac{7}{8} \)

Б) \( \frac{1}{2} + \frac{1}{3} + \frac{1}{6} = \frac{3}{6} + \frac{2}{6} + \frac{1}{6} = \frac{6}{6} = 1 \)

B) \( \frac{1}{3} + \frac{1}{4} + \frac{1}{2} = \frac{4}{12} + \frac{3}{12} + \frac{6}{12} = \frac{13}{12} \)

Г) \( \frac{1}{3} + \frac{1}{4} + \frac{1}{12} = \frac{4}{12} + \frac{3}{12} + \frac{1}{12} = \frac{8}{12} = \frac{2}{3} \)

Д) \( \frac{1}{3} + \frac{1}{5} + \frac{1}{15} = \frac{5}{15} + \frac{3}{15} + \frac{1}{15} = \frac{9}{15} = \frac{3}{5} \)

E) \( \frac{1}{2} + \frac{3}{7} + \frac{5}{14} = \frac{7}{14} + \frac{6}{14} + \frac{5}{14} = \frac{18}{14} = \frac{9}{7} \)

E) \( \frac{1}{4} + \frac{3}{5} + \frac{7}{7} = \frac{1}{4} + \frac{3}{5} + 1 = \frac{5}{20} + \frac{12}{20} + 1 = \frac{17}{20} + 1 = 1\frac{17}{20} \)

Ж) \( \frac{1}{4} + \frac{1}{3} + \frac{1}{5} = \frac{15}{60} + \frac{20}{60} + \frac{12}{60} = \frac{47}{60} \)

3) \( \frac{2}{3} + \frac{1}{2} + \frac{3}{7} = \frac{28}{42} + \frac{21}{42} + \frac{18}{42} = \frac{67}{42} \)

И) \( \frac{3}{4} + \frac{11}{12} + \frac{4}{5} = \frac{45}{60} + \frac{55}{60} + \frac{48}{60} = \frac{148}{60} = \frac{37}{15} \)

K) \( \frac{7}{8} + \frac{14}{15} + \frac{15}{16} = \frac{210}{240} + \frac{224}{240} + \frac{225}{240} = \frac{659}{240} \)

Л) \( 4\frac{15}{49} - 2\frac{3}{14} = \frac{196+15}{49} - \frac{28+3}{14} = \frac{211}{49} - \frac{31}{14} = \frac{422}{98} - \frac{217}{98} = \frac{205}{98} = 2\frac{9}{98} \)

M) \( 5\frac{7}{12} - 2\frac{2}{15} = \frac{67}{12} - \frac{32}{15} = \frac{335}{60} - \frac{128}{60} = \frac{207}{60} = \frac{69}{20} = 3\frac{9}{20} \)

O) \( \frac{11}{14} - \frac{3}{7} = \frac{11}{14} - \frac{6}{14} = \frac{5}{14} \)

И) \( \frac{3}{5} + 3 + \frac{1}{7} = \frac{21}{35} + \frac{105}{35} + \frac{5}{35} = \frac{131}{35} \)

P) \( 3\frac{13}{44} - 1\frac{7}{33} = \frac{132+13}{44} - \frac{33+7}{33} = \frac{145}{44} - \frac{40}{33} = \frac{435}{132} - \frac{160}{132} = \frac{275}{132} = \frac{25}{12} = 2\frac{1}{12} \)

T) \( 2\frac{5}{5} - 1\frac{6}{7} = 2+1 - 1\frac{6}{7} = 3 - 1\frac{6}{7} = 1\frac{1}{7} \)