Помогите решить 6 примеров -3/4•5/7=? -1/3•(-9/13)=? 3/4•(-16)=? -6:5/6=? -7/8:7=? -3...

Решите задачу:

$- \frac{3}{4} \times \frac{5}{7} = - \frac{15}{28}$

$- \frac{1}{3} \times ( - \frac{9}{13} ) = \frac{9}{39} = \frac{3}{1 3}$

$\frac{3}{4} \times ( - 16) = 3 \times ( - 4) = - 12$

$- 6 \div \frac{5}{6} = - 6 \times \frac{6}{5} = - \frac{36}{5} = - 7.2$

$- \frac{7}{8} \div 7 = - \frac{7}{8} \times \frac{1}{7} = - \frac{1}{8} = - 0.125$

$- 3 \frac{4}{9} \div ( - 1 \frac{13}{18} ) = - \frac{31}{9} \div ( - \frac{31}{18} ) =$
$= - \frac{31}{9} \times( - \frac{18}{31} ) = 2$