TOPIC 7 · GRADE 4 FOUNDATION
Add and Subtract Like Denominators
Combine or remove equal-sized parts, including answers greater than one.
MA.4.FR.2.2BIG IDEA
When denominators match, the pieces have the same name and size, so add or subtract their counts while the denominator stays the same.
WHAT TO KNOW
- 3/8 + 4/8 means three eighths plus four eighths, or seven eighths.
- The denominator stays fixed because the size of each piece has not changed.
- A result such as 9/6 can regroup as 1 3/6.
WATCH OUT
Do not add denominators in like-denominator addition; eighths plus eighths are still eighths.
TRY IT
Combine two colored sets of equal-size pieces in one bar.