6 3 28 7 9 30

\[ \frac{6}{7} \div \frac{3}{9} \div \frac{28}{30} = \frac{6}{7} \cdot \frac{9}{3} \cdot \frac{30}{28} = \frac{6 \cdot 9 \cdot 30}{7 \cdot 3 \cdot 28} = \frac{1620}{588} = \frac{135}{49} = 2\frac{37}{49} \]

Ответ: \(2\frac{37}{49}\)