3.NF.A.2
Understand a fraction as a number on the number line; represent fractions on a number line diagram.
3.NF.A.3.a
Understand two fractions as equivalent (equal) if they are the same size, or the same point on a number line.
3.NF.A.3.b
Recognize and generate simple equivalent fractions, e.g., 1/2 = 2/4, 4/6 = 2/3. Explain why the fractions are equivalent, e.g., by using a visual fraction model.