Question

Найдите неизвестный член пропорции ?:2 1/5=1.3:0.26

Answer 1

$\frac{x}{2 \frac{1}{5} } = \frac{1.3}{0.26} \\ 0.26x = 1.3 \times 2.2 \\ 0.26x = 2.86 \\ x = \frac{2.86}{0.26} \\ x = \frac{286}{26} \\ x = 11$
Ответ: 11