Adding Fractions with Like Denominators
Adding fractions with like denominators means combining parts that are already the same size. When the denominators match, the fractions represent equal pieces of a whole, so they can be added directly without rewriting.
How It Works
Confirm matching denominators
Confirm the denominators match.
$$
\frac{a}{b} \text{ and } \frac{c}{b}
$$
Add the numerators
Add the numerators.
$$
a + c
$$
Keep the denominator the same
Keep the denominator unchanged.
$$
\frac{a+c}{b}
$$
Try These Examples
Add. $$ $$ Add. $$ $$ Add. $$ $$
\frac{3}{7} + \frac{2}{7}
$$
\frac{5}{7}
$$
\frac{4}{9} + \frac{3}{9}
$$
\frac{7}{9}
$$
\frac{7}{6} + \frac{5}{6}
$$
\frac{12}{6}
$$
Watch Out
Common Mistake
Some students add both the numerators and the denominators when the fractions already have matching denominators.
Incorrect:
$$
\frac{2}{5} + \frac{3}{5} = \frac{5}{10}
$$
Some students add both the numerators and the denominators when the fractions already have matching denominators.
Incorrect:
$$
\frac{2}{5} + \frac{3}{5} = \frac{5}{10}
$$
Keep Practicing
Try these related worksheets to build fluency and confidence.
Pizza or Tacos Opinion Writing Worksheets (Differentiated K–3)
Summer or Winter Opinion Writing Worksheets (Differentiated K–3)
Equivalent Fraction Wall Anchor Chart Worksheet
