Add 21/30 and 15/18
21/30 + 15/18 is 23/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
15/18 = 15 × 5/18 × 5 = 75/90 - Add the two like fractions:
63/90 + 75/90 = 63 + 75/90 = 138/90 - 138/90 simplified gives 23/15
- So, 21/30 + 15/18 = 23/15
In mixed form: 18/15
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