Provide your best answer for the following math problem. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The problem is: a certain fraction has the same ratio to 1 / 36 , as 4 / 7 does to 5 / 9 . what is this certain fraction ?
1 / 35
1/9.