Variables and Algebraic Expressions: Unlike denominators with variables

$\frac{2}{5}x+\frac{4}{3}y+\frac{7}{9}x+\frac{3}{4}y=\text{?}$

$1\frac{8}{45}x+2\frac{1}{12}y$

$\frac{2}{3}a+\frac{1}{4}b+\frac{1}{8}c+\frac{1}{4}a=\text{?}$

$\frac{11}{12}a+\frac{1}{4}b+\frac{1}{8}c$

$\frac{4}{7}x+\frac{5}{7}y+\frac{3}{4}x+\frac{8}{9}y=\text{?}$

$1\frac{9}{28}x+1\frac{38}{63}y$

$\frac{3z}{4}+\frac{1}{4}m+\frac{12}{13}z\cdot\frac{4}{5}m+\frac{1}{7}z=\text{?}$

^{$\frac{25}{28}z+\frac{1}{4}m+\frac{48}{65}zm$}

^{$3\frac{b}{a}\cdot1\frac{3}{8}a+\frac{5}{8}b+\frac{4}{18}m+\frac{9}{10}a+\frac{2}{3}m=\text{?}$}

$4\frac{3}{4}b+\frac{9}{10}a+\frac{8}{9}m$

^{$(\frac{3}{4}+2a)(8a+9ba)-(5+a)(\frac{3}{2}a+b)=\text{?}$}

_{^{$-\frac{3}{2}a+5\frac{3}{4}ab+14\frac{1}{2}a^2+(18a^2-5)b$}}