You need the indefinite article and a preposition in your sentence. Can you work out where they should go?
We have got an eight to the ten ratio men to the women.
OK, I told you that you needed an indefinite article and you added one. I have marked it above in green. That is correct.
Please show me where I told you that you needed to add any definite articles at all. Why did you add two?
I told you that you needed to add a preposition. You haven't added one.
I am going to make you work on this post, tufguy. We can't just keep handing out answers.
The Cambridge Dictionary has a useful sample sentence.
.an eight-to-ten ratio