Add: $\dfrac{3}{7} + \dfrac{5}{14} + \dfrac{2}{7}$. Show all steps.

L.C.M. of the denominators 7, 14 and 7 :

$\begin{array}{c|ccc} 2 & 7 & 14 & 7 \ \hline 7 & 7 & 7 & 7 \ \hline & 1 & 1 & 1 \ \end{array}$

L.C.M. of the denominators 7, 14 and 7 = 2 × 7 = 14

$\Rightarrow \dfrac{3}{7} + \dfrac{5}{14} + \dfrac{2}{7} \\[1em] = \dfrac{6}{14} + \dfrac{5}{14} + \dfrac{4}{14} \\[1em] = \dfrac{6 + 5 + 4}{14} \\[1em] = \dfrac{15}{14} \\[1em] = 1\dfrac{1}{14}.$

Hence, $\dfrac{3}{7} + \dfrac{5}{14} + \dfrac{2}{7} = 1\dfrac{1}{14}$.