Question

Решите номер 1.Есть вложение.

Answer 1

$\cfrac{13}{1 \frac{2}{3}- \frac{3}{7} } = \cfrac{13}{\frac{5}{3}- \frac{3}{7} } = \cfrac{13}{\frac{35}{21}- \frac{9}{21} } =\cfrac{13}{\frac{35-9}{21} } = \cfrac{13}{\frac{26}{21} } =\cfrac{13\cdot21}{26 } =\cfrac{21}{2 } =10.5$