Question Number 62049 by hhghg last updated on 14/Jun/19
$$\frac{\mathrm{1}}{\mathrm{4}}+\frac{\mathrm{1}}{\mathrm{5}} \\ $$
Commented by maxmathsup by imad last updated on 15/Jun/19
$$=\frac{\left(\mathrm{1}×\mathrm{5}\right)+\left(\mathrm{4}×\mathrm{1}\right)}{\mathrm{4}×\mathrm{5}}\:=\frac{\mathrm{5}+\mathrm{4}}{\mathrm{20}}\:=\frac{\mathrm{9}}{\mathrm{20}} \\ $$