tolong jawab ya dengan caranya

9 + 9 =18
\frac{11}{9} [/tex] =1 [tex] \frac{3}{9} [/tex]
18 + 1 = 19
[tex] \frac{6}{7}+ \frac{3}{9}= 7 X 9 = 63 = \frac{54}{63} + \frac{21}{63} [/tex]