3 3/5 : X=6 4/5 : 1 1/3 7 1/3 : 2 1/2 =3 2/3 : y 4 2/5 : X=8 4/5 : 2 1/2. 6 1/2 * 3 3/4 = 3 1/4 : y

Решим пропорции:

1. $$3 \frac{3}{5} : X = 6 \frac{4}{5} : 1 \frac{1}{3}$$

   $$X = \frac{3 \frac{3}{5} \cdot 1 \frac{1}{3}}{6 \frac{4}{5}} = \frac{\frac{18}{5} \cdot \frac{4}{3}}{\frac{34}{5}} = \frac{\frac{72}{15}}{\frac{34}{5}} = \frac{72}{15} \cdot \frac{5}{34} = \frac{72}{3} \cdot \frac{1}{34} = \frac{24}{34} = \frac{12}{17}$$

   Ответ: $$X=\frac{12}{17}$$

2. $$7 \frac{1}{3} : 2 \frac{1}{2} = 3 \frac{2}{3} : y$$

   $$y = \frac{2 \frac{1}{2} \cdot 3 \frac{2}{3}}{7 \frac{1}{3}} = \frac{\frac{5}{2} \cdot \frac{11}{3}}{\frac{22}{3}} = \frac{\frac{55}{6}}{\frac{22}{3}} = \frac{55}{6} \cdot \frac{3}{22} = \frac{5}{2} \cdot \frac{1}{2} = \frac{5}{4} = 1 \frac{1}{4}$$

   Ответ: $$y=1 \frac{1}{4}$$

3. $$4 \frac{2}{5} : X = 8 \frac{4}{5} : 2 \frac{1}{2}$$

   $$X = \frac{4 \frac{2}{5} \cdot 2 \frac{1}{2}}{8 \frac{4}{5}} = \frac{\frac{22}{5} \cdot \frac{5}{2}}{\frac{44}{5}} = \frac{\frac{110}{10}}{\frac{44}{5}} = \frac{11}{\frac{44}{5}} = 11 \cdot \frac{5}{44} = \frac{5}{4} = 1 \frac{1}{4}$$

   Ответ: $$X=1 \frac{1}{4}$$

4. $$6 \frac{1}{2} \cdot 3 \frac{3}{4} = 3 \frac{1}{4} : y$$

   $$y = \frac{3 \frac{1}{4}}{6 \frac{1}{2} \cdot 3 \frac{3}{4}} = \frac{\frac{13}{4}}{\frac{13}{2} \cdot \frac{15}{4}} = \frac{\frac{13}{4}}{\frac{195}{8}} = \frac{13}{4} \cdot \frac{8}{195} = \frac{2}{15}$$

   Ответ: $$y=\frac{2}{15}$$