Cách làm cho bạn:
$\frac{2}{5}\times \frac{3}{8}+\frac{3}{4}=\frac{6}{40}+\frac{3}{4}=\frac{6}{40}+\frac{30}{40}=\frac{36}{40}$
$\frac{2}{5}+ \frac{3}{8}\times\frac{3}{4}=\frac{2}{5}+\frac{9}{32}=\frac{64}{160}+\frac{45}{160}=\frac{109}{160}$
$\frac{3}{4}: \frac{1}{5}-\frac{1}{3}=\frac{3}{4}\times \frac{5}{1}-\frac{1}{3}=\frac{15}{4}- \frac{1}{3}=\frac{41}{12}$
$\frac{3}{4}- \frac{1}{5}:\frac{1}{3}=\frac{3}{4}-\frac{1}{5}\times \frac{3}{1}=\frac{3}{4}- \frac{3}{5}=\frac{3}{20}$
Bình luận