Решите:
Дроби:
б)-3/4*16/21
в)(-7/9):(-14/45)

[tex]- \frac{3}{4} * \frac{16}{21} =-( \frac{3*16}{4*21} )=- \frac{4}{7} [/tex]

[tex](- \frac{7}{9}): (-\frac{14}{45})= \frac{7*45}{9*14} = \frac{5}{2} =2 \frac{1}{2} =2,5[/tex]