\[\boxed{\mathbf{2.425}}\]
Пояснение.
Решение.
\[\textbf{а)}\ 10 \cdot \frac{1}{10} = 1\]
\[\textbf{б)}\ \frac{1}{6} \cdot 6 = 1\]
\[\textbf{в)}\ \frac{5}{9} \cdot \frac{9}{5} = 1\]
\[\textbf{г)}\ \frac{3}{8} \cdot \frac{8}{3} = 1\]
\[\textbf{д)}\ \frac{5}{12} \cdot 2\frac{2}{5} = \frac{5}{12} \cdot \frac{12}{5} = 1\]
\[\textbf{е)}\ 2\frac{5}{6} \cdot \frac{6}{17} = \frac{17}{6} \cdot \frac{6}{17} = 1\]
\[\textbf{ж)}\ \frac{4}{15} \cdot 3,75 = \frac{4}{15} \cdot \frac{375}{100} =\]
\[= \frac{4}{15} \cdot \frac{15}{4} = 1\]
\[\textbf{з)}\ 0,6 \cdot 1\frac{2}{3} = \frac{6}{10} \cdot \frac{5}{3} = \frac{3}{5} \cdot \frac{5}{3} = 1\]