Номер 627 вычислите пожалуйста даю 70 балов

Ответ:

1) 1/2; 2) 2/3; 3) 2

Пошаговое объяснение:

$1) \dfrac{\frac{3}{8} +\frac{1}{12} +\frac{1}{6} }{\frac{1}{12}+\frac{1}{3} +\frac{5}{6}} =\dfrac{\frac{9}{24} +\frac{2}{24} +\frac{4}{24}}{\frac{1}{12}+\frac{4}{12} +\frac{10}{12} }= \dfrac{\frac{15}{24} }{\frac{15}{12} }=\dfrac{15*12}{24*15} =\dfrac{1}{2}$

$2)\dfrac{\frac{2}{3} -\frac{1}{6} -\frac{4}{9}}{\frac{7}{9}-\frac{5}{12} -\frac{5}{18} }=\dfrac{\frac{12}{18} -\frac{3}{18} -\frac{8}{18}}{\frac{28}{36}-\frac{15}{36} -\frac{10}{36} }=\dfrac{\frac{1}{18} }{\frac{3}{36} } =\dfrac{1*36}{18*3} =\dfrac{2}{3}$

$3)\dfrac{2\frac{1}{4} *1\frac{1}{3} *\frac{8}{9}}{1\frac{1}{5}*\frac{4}{9}*2\frac{1}{2} }=\dfrac{\frac{9}{4} *\frac{4}{3} *\frac{8}{9}}{\frac{6}{5}*\frac{4}{9}*\frac{5}{2} }=\dfrac{\frac{8}{3} }{\frac{4}{3} } =\dfrac{8*3}{3*4} =2$