6.NS.A.1 math practice. Learn by doing.

Multiply by the reciprocal: $\dfrac{3}{9} \times \dfrac{8}{5} = \dfrac{24}{45} = \dfrac{8}{15}$.

Multiply across: $\dfrac{3 \times 3}{6 \times 7} = \dfrac{9}{42} = \dfrac{3}{14}$.

Multiply by the reciprocal: $\dfrac{3}{4} \times \dfrac{3}{2} = \dfrac{9}{8} = \dfrac{9}{8}$.

Multiply across: $\dfrac{3 \times 6}{6 \times 7} = \dfrac{18}{42} = \dfrac{3}{7}$.

Multiply by the reciprocal: $\dfrac{3}{7} \times \dfrac{7}{3} = \dfrac{21}{21} = \dfrac{1}{1}$.

Multiply across: $\dfrac{3 \times 1}{5 \times 6} = \dfrac{3}{30} = \dfrac{1}{10}$.

Multiply by the reciprocal: $\dfrac{5}{6} \times \dfrac{5}{3} = \dfrac{25}{18} = \dfrac{25}{18}$.

Multiply across: $\dfrac{3 \times 5}{6 \times 8} = \dfrac{15}{48} = \dfrac{5}{16}$.