Задание 7. Составим из двух равных произведений 4 верные пропорции.
$$3 \cdot 12 = 9 \cdot 4$$
$$36 = 36$$
Пропорции:
$$\frac{3}{9} = \frac{4}{12}; \frac{3}{4} = \frac{9}{12}; \frac{12}{9} = \frac{4}{3}; \frac{12}{4} = \frac{9}{3}$$
$$4 \cdot 15 = 6 \cdot 10$$
$$60 = 60$$
Пропорции:
$$\frac{4}{6} = \frac{10}{15}; \frac{4}{10} = \frac{6}{15}; \frac{15}{6} = \frac{10}{4}; \frac{15}{10} = \frac{6}{4}$$
Ответ: 1) $$\frac{3}{9} = \frac{4}{12}; \frac{3}{4} = \frac{9}{12}; \frac{12}{9} = \frac{4}{3}; \frac{12}{4} = \frac{9}{3}$$; 2) $$\frac{4}{6} = \frac{10}{15}; \frac{4}{10} = \frac{6}{15}; \frac{15}{6} = \frac{10}{4}; \frac{15}{10} = \frac{6}{4}$$