\(a)\frac{7}{25}:\frac{14}{5}+\frac{15}{4}\times\frac{1}{5}\)
\(=\frac{7}{25}\times\frac{5}{14}+\frac{15}{4}\times\frac{1}{5}\)
\(=\frac{1}{10}+\frac{3}{4}\)
\(=\frac{17}{20}\)
\(b)\frac{4}{7}\times\frac{21}{8}-\frac{1}{7}:\frac{14}{5}\)
\(=\frac{4}{7}\times\frac{21}{8}-\frac{1}{7}\times\frac{5}{14}\)
\(=\frac{3}{2}-\frac{5}{98}\)
\(=\frac{71}{49}\)
b4/7x21/8-1/7:14/5
=4/7x21/8-1/7x5/14
=84/56-5/98
=3/2-5/98
=71/49
mk giải câu b thôi nha
a) 7/25:14/5+15/4x1/5
=7/25x5/14+3/4
=1/10+3/4
=17/20
b) 4/7x21/8-1/7:14/5
=3/2-1/7:5/14
=3/2-5/98
=71/49
\(\frac{7}{25}:\frac{14}{5}+\frac{15}{4}\times\frac{1}{5}\)
\(=\frac{7}{25}\times\frac{5}{14}+\frac{3}{4}\times\frac{1}{1}\)
\(=\frac{1}{5}\times\frac{1}{1}+\frac{3}{4}\)
\(=\frac{1}{5}+\frac{3}{4}\)
\(=\frac{4}{20}+\frac{15}{20}\)
\(=\frac{19}{20}\)
\(\frac{4}{7}\times\frac{21}{8}-\frac{1}{7}:\frac{14}{5}\)
\(=\frac{1}{1}\times\frac{3}{2}-\frac{1}{7}\times\frac{5}{14}\)
\(=\frac{3}{2}-\frac{5}{98}\)
\(=\frac{294}{196}-\frac{10}{196}\)
\(=\frac{284}{196}\)