Resposta :
[tex]0,777... = \boxed{\frac{7}{9}}[/tex]
[tex]3,888... = 3 + \frac{8}{9}[/tex]
(MMC = 9)
[tex]\frac{27}{9} + \frac{8}{9} = \boxed{\frac{35}{9}}[/tex]
0,777 10X -------- 07,777
-X ------- 0,777
9X ------ 7,000
X = 7/9
3,888 10X ----------- 38,888
-X ----------- 3,888
9X ----------- 35,000
X= 35/9