$1\ +\frac{1}{x}\ \rightarrow\frac{x}{x}\ +\frac{1}{x}\rightarrow\frac{x\ +1}{x}$  

 $1\ +\ \frac{1}{x}\rightarrow\ \frac{1}{x}\ +\frac{1}{x\ }\ \rightarrow\ \frac{2}{x}$  

 $\frac{5}{2}-\frac{4}{m}\ \ \rightarrow\ \ \ \frac{5}{2m}\ \ -\ \ \frac{4}{2m}\ \ \rightarrow\ \ \ \frac{5\ -4}{2m}\ \rightarrow\ \ \ \frac{1}{2m}$  

 $\frac{5}{2}-\frac{4}{m}=\frac{5m}{2m}\ -\ \frac{8}{2m}\ =\ \frac{5m\ -\ 8}{2m}$  

 $\frac{4}{y}+\frac{y}{4}=\frac{16}{4y}+\frac{y^2}{4y}=\frac{16\ +y^2}{4y}$  

 $\frac{4}{y}+\frac{y^2}{4}=\frac{16}{4y}+\frac{y}{4y}=\frac{16\ +y^2}{4y}$