Add 12/9 and 7/21
1st number: 1 3/9, 2nd number: 7/21
12/9 + 7/21 is 5/3.
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,
7/21 = 7 × 3/21 × 3 = 21/63 - Add the two like fractions:
84/63 + 21/63 = 84 + 21/63 = 105/63 - 105/63 simplified gives 5/3
- So, 12/9 + 7/21 = 5/3
In mixed form: 12/3
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