\(\dfrac{9}{11}\)x\(\dfrac{1}{3}=\dfrac{9x1}{11x3}=\dfrac{9}{33}=\dfrac{3}{11}\)

=\(\dfrac{12}{7}-\dfrac{3}{2}\)

=\(\dfrac{3}{8}\)

\(\dfrac{7}{20}:x=\dfrac{3}{5}\)

        \(x=\dfrac{7}{20}:\dfrac{3}{5}\)

        \(x=\dfrac{7}{12}\)

\(\dfrac{20}{11},\dfrac{15}{11},\dfrac{20}{27},\dfrac{4}{7}\)

c.\(\dfrac{8}{7},\dfrac{7}{6}\)

c.\(\dfrac{1}{10}\) giờ

c.\(\dfrac{16}{15}\) là phân số đã tối giản

\(\dfrac{6}{14}-\dfrac{3}{7}=\dfrac{6}{14}-\dfrac{6}{14}=0\)

1508

20 tấn 4 kg =20004kg

1 tấn = 1000kg 

20 tấn = 20000 kg +4kg = 20004kg