Question

7/21(3/9×4/20)÷4/6-8/9

Answer 1

$\frac{7}{21} \times ( \frac{3}{9} \times \frac{4}{20} ) \div \frac{4}{6} - \frac{8}{9} = \\ \\ \frac{1}{3} \times ( \frac{1}{3} \times \frac{1}{5} ) \times \frac{4}{4} - \frac{8}{9} = \\ \\ \frac{1}{3} \times \frac{1}{15} \times \frac{3}{2 -} - \frac{8}{9} = \\ \\ \frac{1}{15} \times \frac{1}{2} - \frac{8}{9} = \\ \\ \frac{1}{30} - \frac{8}{9} \\ \\ = - \frac{77}{90}$