Решите.Срочно.даю 40 балов.все уравнения

Вариант Б2

а) $(3 \frac{2}{3} - 1,8) : 2 \frac{4}{5} = (\frac{11}{3} - \frac{9}{5} ) : \frac{14}{5} = \frac{55-27}{15} : \frac{14}{5} = \frac{28}{15} : \frac{14}{5} = \frac{28*5}{15*14} = \frac{2}{3}$

б) $( \frac{3}{4} + 4 \frac{2}{3}* \frac{9}{56})*1 \frac{2}{3} = (\frac{3}{4} + \frac{14}{3}* \frac{9}{56})* \frac{5}{3} = ( \frac{3}{4} + \frac{14*9}{3*56})* \frac{5}{3} = ( \frac{3}{4} + \frac{3}{4}) * \frac{5}{3}$ $= \frac{6}{4} * \frac{5}{3} = \frac{6*5}{4*3} = \frac{5}{2} = 2 \frac{1}{2}$

Вариант В2

а) $(5 - 1 \frac{1}{3}*1 \frac{1}{6})* \frac{27}{31} = (5 - \frac{4}{3} * \frac{7}{6}) * \frac{27}{31} = (5 - \frac{4*7}{3*6}) * \frac{27}{31} = (5 - \frac{14}{9})* \frac{27}{31}$ $= ( \frac{45-14}{9})* \frac{27}{31} = \frac{31}{9}* \frac{27}{31} = \frac{31*27}{9*31} = \frac{27}{9} = 3$

б) $(4,1 - 2 \frac{3}{4} ):(1 \frac{16}{21} + 4 \frac{2}{3}) = ( \frac{41}{10} - \frac{11}{4}) : ( \frac{37}{21} + \frac{14}{3}) = (\frac{82-55}{20}) : ( \frac{37+98}{21})$ $= \frac{27}{20} : \frac{135}{21} = \frac{27*21}{20*135} = \frac{21}{20*5} = \frac{21}{100}$

Удачи!