Помогите пожалуйста номер 639 2,4,6 дою 10баллов

2) ( $\frac{4}{15}$ + $\frac{2}{3}$ ) ÷ $\frac{2}{5}$ =
( $\frac{4}{15}$ + $\frac{10}{15}$ ) ÷ $\frac{2}{5}$ =
$\frac{14}{15}$ ÷ $\frac{2}{5}$ = $\frac{7}{3}$ =2 $\frac{1}{3}$

4) $\frac{8}{11}$ ×( $\frac{5}{6}$ - $\frac{3}{8}$ )=
$\frac{8}{11}$ ×( $\frac{20}{24}$ - $\frac{9}{24}$ )=
$\frac{8}{11}$ × $\frac{11}{24}$ = $\frac{1}{3}$

6) $\frac{3}{8}$ ×( $\frac{7}{12}$ + $\frac{3}{4}$ )=
$\frac{3}{8}$ ×( $\frac{7}{12}$ + $\frac{9}{12}$ )=
$\frac{3}{8}$ × $\frac{16}{12}$ = $\frac{1}{2}$