a)$\text{3}$$\dfrac{1}{2}$+$\text{2}$$\dfrac{2}{5}$
= $\dfrac{7}{2}$+$\dfrac{12}{5}$
=$\dfrac{59}{10}$
b)$\text{6}$$\dfrac{3}{4}$x$\text{1}$$\dfrac{7}{13}$
=$\dfrac{27}{4}$x$\dfrac{20}{13}$
=$\dfrac{135}{13}$
c)$\text{5}$$\dfrac{3}{8}$-$\text{1}$$\dfrac{5}{6}$
=$\dfrac{43}{8}$-$\dfrac{11}{6}$
=$\dfrac{85}{24}$
d)$\text{9}$$\dfrac{5}{6}$:$\text{8}$$\dfrac{1}{7}$
=$\dfrac{59}{6}$:$\dfrac{57}{7}$
=$\dfrac{413}{342}$
