Question

1/5+[7/9:(1/2.2/4-1/9)]

Answer 1

1/5+[7/9:(1/2.2/4-1/9)]=
1/5+[7/9:(2/8-1/9)]=
1/5+[7/9:(18/72-8/72)]=
1/5+[7/9:10/72]=
1/5+[7/9.72/10]=
1/5+[504/90]=
18/90+504/90=
522/90=  (simplificando por 9)
58/10