Tính nhanh: d) 3/8 : ( 7/22 − 2/11 ) + 3/8 : ( 2/5 − 1/10 )

d) $\frac{3}{8}:(\frac{7}{22}-\frac{2}{11})+\frac{3}{8}:(\frac{2}{5}-\frac{1}{10})$

$=\frac{3}{8}:(\frac{7}{22}-\frac{4}{22})+\frac{3}{8}:(\frac{4}{10}-\frac{1}{10})$

$=\frac{3}{8}:\frac{3}{22}+\frac{3}{8}:\frac{3}{10}$

$=\frac{3}{8}.(\frac{22}{3}+\frac{10}{3})=\frac{3}{8}.\frac{32}{3}=4$