Add 21/12 and 15/30
1st number: 1 9/12, 2nd number: 15/30
21/12 + 15/30 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
15/30 = 15 × 2/30 × 2 = 30/60 - Add the two like fractions:
105/60 + 30/60 = 105 + 30/60 = 135/60 - 135/60 simplified gives 9/4
- So, 21/12 + 15/30 = 9/4
In mixed form: 21/4
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