Ответ:
\(\frac{1}{7}+\frac{6}{49}=\frac{7}{49}+\frac{6}{49}=\frac{13}{49}\).
\(\frac{7}{39}\cdot\frac{13}{49}=\frac{1}{21}\).
Ответ: \(\frac{1}{21}\)
\(\frac{1}{7}+\frac{6}{49}=\frac{7}{49}+\frac{6}{49}=\frac{13}{49}\).
\(\frac{7}{39}\cdot\frac{13}{49}=\frac{1}{21}\).
Ответ: \(\frac{1}{21}\)