710. При каких значениях р значение дроби \frac{3-1,2p}{4} равно: a) 0; 6) -1; B) -$$\frac{1}{12}$$; г) 0,7?

a) Решим уравнение $$\frac{3-1,2p}{4} = 0$$: $$3 - 1.2p = 0$$ $$1.2p = 3$$ $$p = \frac{3}{1.2} = \frac{30}{12} = \frac{5}{2} = 2.5$$ б) Решим уравнение $$\frac{3-1,2p}{4} = -1$$: $$3 - 1.2p = -4$$ $$1.2p = 7$$ $$p = \frac{7}{1.2} = \frac{70}{12} = \frac{35}{6} = 5\frac{5}{6}$$ в) Решим уравнение $$\frac{3-1,2p}{4} = -\frac{1}{12}$$: $$3 - 1.2p = -\frac{4}{12} = -\frac{1}{3}$$ $$1.2p = 3 + \frac{1}{3} = \frac{10}{3}$$ $$p = \frac{10}{3 \cdot 1.2} = \frac{10}{3.6} = \frac{100}{36} = \frac{25}{9} = 2\frac{7}{9}$$ г) Решим уравнение $$\frac{3-1,2p}{4} = 0.7$$: $$3 - 1.2p = 4 \cdot 0.7 = 2.8$$ $$1.2p = 3 - 2.8 = 0.2$$ $$p = \frac{0.2}{1.2} = \frac{2}{12} = \frac{1}{6}$$ Ответ: a) 2,5; б) $$5\frac{5}{6}$$; в) $$2\frac{7}{9}$$; г) $$\frac{1}{6}$$