Read it out loud, and write down what you hear yourself say.
After that, you can simplify the fraction if you want to.
When you read ' 0.5 ' out loud, you should say "five tenths".
When you hear that, you would write down
5/10 .
If you want to simplify it, then you can divide the numerator
and the denominator both by 5, and you'll end up with
1/2 .