Question

Пж быстрее в тетради 100 баллов

Answer 1

Ответ:

7/144

Пошаговое объяснение:

$\displaystyle\bf\frac{\dfrac{7}{9}:2+\dfrac{7}{10}}{\dfrac{28}{5}:\dfrac{1}{4}}=\frac{\dfrac{7}{18}+\dfrac{7}{10}}{\dfrac{28}{5}*\dfrac{4}{1}}=\\\\\\\\=\frac{\dfrac{7*5+7*9}{90}}{\dfrac{28*4}{5}}=\frac{35+63}{90} *\frac{5}{28*4}=\\\\\\\\=\frac{98}{18*5} *\frac{5}{28*4}= \frac{2*49}{2*9}* \frac{1}{7*4*4}=\\\\\\\\=\frac{7*7}{9} *\frac{1}{7*16} = \frac{7}{9*16}=\frac{7}{144}$

Answer 2

Ответ:

$\frac{ \frac{7}{9} \div 2 + \frac{7}{10} }{ \frac{28}{5} \div \frac{1}{4} } \\ \\ \frac{ \frac{7}{9} \times \frac{1}{2} + \frac{7}{10} }{ \frac{28}{5} \times \frac{4}{1} } \\ \\ \frac{ \frac{7 \times 1}{9 \times 2} + \frac{7}{10} }{ \frac{28 \times 4}{5 \times 1} } \\ \\ \frac{ \frac{7}{18} + \frac{7}{10} }{ \frac{112}{5} } \\ \\ \frac{ \frac{90 \div 18 \times 7}{90} + \frac{90 \div 10 \times 7}{90} }{ \frac{112}{5} } \\ \\ \frac{ \frac{5 \times 7}{90} + \frac{9 \times 7}{90} }{ \frac{112}{5} } \\ \\ \frac{ \frac{35}{90} + \frac{63}{90} }{ \frac{112}{5} } \\ \\ \frac{ \frac{35 + 63}{90} }{ \frac{112}{5} } \\ \\ \frac{ \frac{98}{90} }{ \frac{112}{5} } \\ \\ \frac{ \frac{98 \: \: | \: \div 2 }{90 | \: \div 2} }{ \frac{112}{5} } \\ \\ \frac{ \frac{49}{45} }{ \frac{112}{5} } \\ \\ \frac{49}{45} \div \frac{112}{5} \\ \\ \frac{49}{45} \times \frac{5}{112} \\ \\ \frac{49 \times 5}{45 \times 112} \\ \\ \frac{(49 \div 7 )\times (5 \div 5) }{(45 \div 5) \times (112 \div 7)} \\ \\ \frac{7 \times 1}{9 \times 16} \\ \\ \boxed{ \frac{7}{144} }$