\(\dfrac{3}{10}\) + \(\dfrac{1}{2}\) = \(\dfrac{3}{10}\) + \(\dfrac{5}{10}\) = \(\dfrac{8}{10}\) = \(\dfrac{4}{5}\)
\(\dfrac{5}{2}\) - \(\dfrac{5}{7}\) = \(\dfrac{35}{14}\) - \(\dfrac{10}{14}\) = \(\dfrac{25}{14}\)
3/10+1/2=3/10+5/10=8/10=4/5
5/2-5/7=35/14-10/14=25/14
\(\dfrac{3}{10}\) + \(\dfrac{1}{2}\) = \(\dfrac{3}{10}\) + \(\dfrac{5}{10}\) = \(\dfrac{4}{5}\)
\(\dfrac{5}{2}\) - \(\dfrac{5}{7}\) = \(\dfrac{35}{14}\) - \(\dfrac{10}{14}\) = \(\dfrac{25}{14}\)