6-16

1,5 / (1 + 1/5)

$$ \frac{1,5}{1 + \frac{1}{5}} = \frac{1,5}{\frac{6}{5}} = 1,5 \cdot \frac{5}{6} = \frac{3}{2} \cdot \frac{5}{6} = \frac{15}{12} = \frac{5}{4} = 1,25$$

Ответ: 1,25