How to decide if subject is plural or singular

[elemat]

Which is the correct sentence:
1. One percent of Cleveland's teens is pregnant.
2. One percent of Cleveland's teens are pregnant.

The second sounds better to my ears, but this rule i found indicates that #1 is the correct choice: "Quantifiers: with fractions, percentages, and indefinite quanitfiers, the verb should agree with main subject of the sentence, not the noun contained within the perpositional phrase. With singular or non-count nouns or clauses, use a singular verb. "

[scoobydooby]

would go for #2.

even if fractions are used, fraction of X, it is the X that determines whether the subject is singular or plural.

here X is countable and plural, so we must use "are"