Add 21/12 and 15/81
1st number: 1 9/12, 2nd number: 15/81
21/12 + 15/81 is 209/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 12 × 27 = 324,
21/12 = 21 × 27/12 × 27 = 567/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
15/81 = 15 × 4/81 × 4 = 60/324 - Add the two like fractions:
567/324 + 60/324 = 567 + 60/324 = 627/324 - 627/324 simplified gives 209/108
- So, 21/12 + 15/81 = 209/108
In mixed form: 1101/108
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