\(a,\dfrac{4}{5}\times\dfrac{2}{7}=\dfrac{8}{35}\)

\(b,\dfrac{5}{8}\times3=\dfrac{15}{8}\)

\(c,5\times\dfrac{6}{21}=\dfrac{30}{21}\)

\(d,\dfrac{3}{5}\times\dfrac{4}{5}\times\dfrac{6}{7}=\dfrac{72}{175}\)

After brushing my teeth, I go to bed.

\(b,\dfrac{5}{8}\times3=\dfrac{15}{8}\)

\(c,5\times\dfrac{6}{21}=\dfrac{30}{21}\)

\(d,\dfrac{3}{5}\times\dfrac{4}{5}\times\dfrac{6}{7}=\dfrac{72}{175}\)

uhm ... buff chỗ nào ??

The fumes from cars and factories make people cough.

\(a,\dfrac{8}{5}\times\dfrac{1}{4}=\dfrac{2}{5}\)

\(b,\dfrac{2}{5}\times\left(\dfrac{3}{7}+\dfrac{4}{7}\right)=\dfrac{2}{5}\)