Add 15/12 and 25/21
1st number: 1 3/12, 2nd number: 1 4/21
15/12 + 25/21 is 205/84.
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,
25/21 = 25 × 4/21 × 4 = 100/84 - Add the two like fractions:
105/84 + 100/84 = 105 + 100/84 = 205/84 - So, 15/12 + 25/21 = 205/84
In mixed form: 237/84
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