Resposta :
0,3888... = x
3,888... = 10x
38,888 = 100x
100x - 10x = 38,888... - 3,888...
90x = 35
x = 35/90
x = 7/18
como achar a geratriz de 0,38888...
0,3888... = x
3,888... = 10x
38,888 = 100x
100x - 10x = 38,888... - 3,888...
90x = 35
x = 35/90
x = 7/18