\[ \frac{2}{7} + \frac{3}{4} = \frac{2 \times 4}{7 \times 4} + \frac{3 \times 7}{4 \times 7} = \frac{8}{28} + \frac{21}{28} = \frac{8 + 21}{28} = \frac{29}{28} \]
\[ \frac{29}{7} \times \frac{29}{28} = \frac{29 \times 29}{7 \times 28} = \frac{841}{196} \]
Ответ: \[ \frac{841}{196} \]