Add 15/12 and 30/21
1st number: 1 3/12, 2nd number: 1 9/21
15/12 + 30/21 is 75/28.
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,
30/21 = 30 × 4/21 × 4 = 120/84 - Add the two like fractions:
105/84 + 120/84 = 105 + 120/84 = 225/84 - 225/84 simplified gives 75/28
- So, 15/12 + 30/21 = 75/28
In mixed form: 219/28
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