Add the following:

 $\frac{2}{5}+\frac{1}{3}$  

(a)  

Add the following:

 $\frac{5}{7}+\frac{1}{4}$  

(a)  

Subtract these fractions:

 $\frac{4}{7}-\frac{2}{5}$  

(a)  

Subtract the following:

 $\frac{10}{12}-\frac{3}{8}$  

(a)  

Subtract the following:

 $\frac{7}{11}-\frac{2}{7}$  

(a)