Add 15/12 and 3/21
1st number: 1 3/12, 2nd number: 3/21
15/12 + 3/21 is 39/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
3/21 = 3 × 4/21 × 4 = 12/84 - Add the two like fractions:
105/84 + 12/84 = 105 + 12/84 = 117/84 - 117/84 simplified gives 39/28
- So, 15/12 + 3/21 = 39/28
In mixed form: 111/28
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