Respostas

2014-02-26T20:56:47-03:00
X = 7,5818181... (x10)
10x = 75, 818181...
10x = 75 + 0,818181...
10x = 75 + 81/99
Tirando o MMC e cancelando as bases fica :
990x = 7425 + 81
990x = 7506
x = 7506/990
4 2 4