\(3\dfrac{2}{7}-\dfrac{2}{5}+\dfrac{5}{7}-\dfrac{3}{5}\)
\(=\dfrac{23}{7}-\dfrac{2}{5}+\dfrac{5}{7}-\dfrac{3}{5}\)
\(=\left[\dfrac{23}{7}+\dfrac{5}{7}\right]+\left[\left(\dfrac{-2}{5}\right)+\left(\dfrac{-3}{5}\right)\right]\)
\(=4+\left(-1\right)\)
\(=3\)
\(=3+\dfrac{2}{7}+\dfrac{5}{7}-\dfrac{2}{5}-\dfrac{3}{5}=3+1-1=3\)
=3 2/7 - 2/5 + 5/7 - 3,5
=3 + 1 - 1 = 3
3\(\dfrac{2}{7}\) - \(\dfrac{2}{5}\)+ \(\dfrac{5}{7}\) - \(\dfrac{3}{5}\)
= \(\dfrac{23}{7}\) - \(\dfrac{2}{5}\) + \(\dfrac{5}{7}\) - \(\dfrac{3}{5}\)
= ( \(\dfrac{23}{7}\) + \(\dfrac{5}{7}\) ) + ( \(\dfrac{2}{5}\) - \(\dfrac{3}{5}\) )
= \(4+-1\)
= \(3\)