what is 0.34r as a fraction

I assume you want either :

0.3444..... [4s repeating] 

Or 

0.343434.......[ 34 repeating ]

1st case

[  34  - 3] /  90   = 31/90   = 0.344444.........

2nd Case

[34 - 0] / 99  = 34/99  =  0.343434.......

\(0.34r\)

\(\frac{34}{100}r\)

\(\frac{17}{50}r\)