Add 21/12 and 15/27
1st number: 1 9/12, 2nd number: 15/27
21/12 + 15/27 is 83/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 12 × 9 = 108,
21/12 = 21 × 9/12 × 9 = 189/108 - Likewise, for the 2nd fraction, since 27 × 4 = 108,
15/27 = 15 × 4/27 × 4 = 60/108 - Add the two like fractions:
189/108 + 60/108 = 189 + 60/108 = 249/108 - 249/108 simplified gives 83/36
- So, 21/12 + 15/27 = 83/36
In mixed form: 211/36
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