Add 21/7 and 12/9
1st number: 3 0/7, 2nd number: 1 3/9
21/7 + 12/9 is 13/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
21/7 = 21 × 9/7 × 9 = 189/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Add the two like fractions:
189/63 + 84/63 = 189 + 84/63 = 273/63 - 273/63 simplified gives 13/3
- So, 21/7 + 12/9 = 13/3
In mixed form: 41/3
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