Question

What fraction is equivalent to 123.5%?

Answer 1

123 5/100
And if you wanted to simplify that answer it would be 123 1/20 
That mixed fraction is basically just another way to write 123.5 but I believe it could still work.  

Answer 2

Percents are parts of 100, so write it as a fraction over 100:

123.5/100

or

1 47/200