Georgia Standards of Excellence 5th Grade Math Activities MGSE5.NF.4a. Apply and use understanding of multiplication to multiply a fraction or whole number by a fraction. Examples: a/b × q as (a/b)× (q/1) and (a/b)× (c/d)= (ac)/ (bd) Multiply / Divide Fractions. To multiply two fractions with unlike denominators, multiply the numerators and multiply the denominators.