Add 12/9 and 15/21
1st number: 1 3/9, 2nd number: 15/21
12/9 + 15/21 is 43/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63 - Add the two like fractions:
84/63 + 45/63 = 84 + 45/63 = 129/63 - 129/63 simplified gives 43/21
- So, 12/9 + 15/21 = 43/21
In mixed form: 21/21
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