The fourth grade classes are painting designs on tile squares to make a mural. Mrs. Kirk's class painted 3/10
of the mural. Mr. Becker's class painted 21/100 of the
mural. What part of the mural is painted?
You know how to add fractions with parts that are the
same size. You can use equivalent fractions to add
fractions with parts that are not the same size.
Example 1 Find o + 700
STEP I Write to and 200 as a pair of fractions STEP 2 Add
with a common denominator.
Think: Write using fractions with a common
Think: 100 multiple of 10 ose 100
denominator
the common denominator
30 21
Thinkt already
3 3 x
has 100 in the
100 100 100
10
100 denominator
+
Do
10x
Math
Talk
So
of the mural is painted.
100
MATHEMATICAL PRACTICES
Draw Conclusions When adding
tenths and hundredths, can you
100common