Add 21/12 and 15/18
1st number: 1 9/12, 2nd number: 15/18
21/12 + 15/18 is 31/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
15/18 = 15 × 2/18 × 2 = 30/36 - Add the two like fractions:
63/36 + 30/36 = 63 + 30/36 = 93/36 - 93/36 simplified gives 31/12
- So, 21/12 + 15/18 = 31/12
In mixed form: 27/12
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