\(\dfrac{2}{7}+\dfrac{5}{14}+\dfrac{1}{7}+\dfrac{3}{14}\\ =\left(\dfrac{2}{7}+\dfrac{1}{7}\right)+\left(\dfrac{5}{14}+\dfrac{3}{14}\right)\\ =\dfrac{2+1}{7}+\dfrac{5+3}{14}\\ =\dfrac{3}{7}+\dfrac{8}{14}\\ =\dfrac{3}{7}+\dfrac{4}{7}\\ =\dfrac{3+4}{7}\\ =\dfrac{7}{7}=1\)
\(\dfrac{2}{7}+\dfrac{5}{14}+\dfrac{1}{7}+\dfrac{3}{14}\)
\(=\left(\dfrac{2}{7}+\dfrac{1}{7}\right)+\left(\dfrac{5}{14}+\dfrac{3}{14}\right)\)
\(=\dfrac{3}{7}+\dfrac{8}{14}=\dfrac{6}{14}+\dfrac{8}{14}=\dfrac{14}{14}=1\)
` 2/7 + 5/14 + 1/7 + 3/14 `
`= (2/7 + 1/7) + ( 5/14 + 3/14)`
`= 3/7 + 8/14`
`= 6/14 + 8/14 `
`= 14/14 `
`= 1`