6. Выполните действие: a) 5/18 × 0,42; б) 1,75 : 1 1/3; в) 1,69 × 2/39; г) 7/25 : 0.49.

а) $$ \frac{5}{18} \times 0,42 = \frac{5}{18} \times \frac{42}{100} = \frac{5}{18} \times \frac{21}{50} = \frac{1}{6} \times \frac{7}{10} = \frac{7}{60} $$ б) $$1,75 : 1\frac{1}{3} = \frac{175}{100} : \frac{4}{3} = \frac{7}{4} \times \frac{3}{4} = \frac{21}{16} = 1\frac{5}{16} $$ в) $$1,69 \times \frac{2}{39} = \frac{169}{100} \times \frac{2}{39} = \frac{13}{100} \times \frac{2}{3} = \frac{26}{300} = \frac{13}{150} $$ г) $$ \frac{7}{25} : 0,49 = \frac{7}{25} : \frac{49}{100} = \frac{7}{25} \times \frac{100}{49} = \frac{1}{1} \times \frac{4}{7} = \frac{4}{7} $$ Ответ: а) 7/60; б) 21/16; в) 13/150; г) 4/7.