Answer:
It's simplified form is 1:3
Explanation:
1st step: Convert them into fraction i.e.

2nd step: Now check for their HCF i.e 9 so,

And divide it with both the numerator and denominator and the result is,

3rd step: Now convert them into ratio i.e
1:3
Hence, 9:27 simplified format is 1:3 (Ans)