a: =16/20+15/20-6/20=25/20=5/4
b: =3/5-2/5+7/3=1/5+7/3=3/15+35/15=38/15
\(a,\dfrac{4}{5}+\dfrac{3}{4}-\dfrac{3}{10}=\dfrac{16}{20}+\dfrac{15}{20}-\dfrac{6}{20}=\dfrac{25}{20}=\dfrac{5}{4}\\ b,\dfrac{9}{15}-\dfrac{2}{5}+\dfrac{7}{3}=\dfrac{3}{5}-\dfrac{2}{5}+\dfrac{7}{3}=\dfrac{1}{5}+\dfrac{7}{3}=\dfrac{3}{15}+\dfrac{35}{15}=\dfrac{38}{15}\)
a) \(\dfrac{4}{5}+\dfrac{3}{4}-\dfrac{3}{10}=\dfrac{16}{20}+\dfrac{15}{20}-\dfrac{6}{20}=\dfrac{16+15-6}{20}=\dfrac{25}{20}=\dfrac{5}{4}\)
b) \(\dfrac{9}{15}-\dfrac{2}{5}+\dfrac{7}{3}=\dfrac{9}{15}-\dfrac{6}{15}+\dfrac{35}{15}=\dfrac{9-6+35}{15}=\dfrac{38}{15}\)
