Question

мамонте решить пожалуйста

Answer 1

$frac{4}{9} : frac{8}{21}= frac{4}{9} cdot frac{21}{8} = = frac{4}{3cdot 3} cdot frac{3cdot 7}{4cdot 2} = frac{7}{3cdot 2} = frac{7}{6} =1frac{1}{6}\\ frac{0,42}{9,8} = frac{42}{980} = frac{2cdot 21}{2cdot 490} = frac{21}{490} \\0,2- frac{1}{9} = frac{2}{10} - frac{1}{9}= frac{1}{5} - frac{1}{9} = frac{9-5}{5cdot 9} = frac{4}{45} \\4,5: frac{5}{9}=4 frac{5}{10} : frac{5}{9} = 4frac{1}{2} cdot frac{9}{5}= frac{9}{2} cdot frac{9}{5} = frac{81}{10} =8,1$