Research has shown that fraction magnitude and whole number division are important precursors to learning and understanding fractions. Deaf and hard-of-hearing (DHH) students are consistently challenged with learning fractions from K-12 through college. Sixty DHH college students were tested for both their understanding of magnitude between two fractions and their ability to calculate whole number division. The results showed that both understanding the magnitude between two fractions and whole number division are significantly associated with accurately calculating arithmetic functions of fractions with like denominators and different denominators that required them to add, subtract, multiply, and divide two fractions. Understanding fraction magnitude and whole number division were also significantly associated with their self-rated confidence of math performance with fractions. Tangentially, DHH college students' English reading ability was significantly, but modestly associated with their fraction performance.