1. Упрощаем 2,5 : 0,5
\[ 2,5 \times 10 = 25 \]
\[ 0,5 \times 10 = 5 \]
\[ 25 : 5 \]
\[ 25 : 5 = 5 : 1 \]
2. Упрощаем 3/4 : 1/2
\[ \frac{3}{4} : \frac{1}{2} = \frac{3}{4} \times \frac{2}{1} \]
\[ \frac{3 \times 2}{4 \times 1} = \frac{6}{4} \]
\[ \frac{6}{4} = \frac{3}{2} \]
3. Упрощаем 1 1/3 : 2 2/3
\[ 1 \frac{1}{3} = \frac{(1 \times 3) + 1}{3} = \frac{4}{3} \]
\[ 2 \frac{2}{3} = \frac{(2 \times 3) + 2}{3} = \frac{8}{3} \]
\[ \frac{4}{3} : \frac{8}{3} = \frac{4}{3} \times \frac{3}{8} \]
\[ \frac{4 \times 3}{3 \times 8} = \frac{12}{24} = \frac{1}{2} \]
Ответ: 1) 5:1, 2) 3:2, 3) 1:2