Add 18/21 and 12/9
1st number: 18/21, 2nd number: 1 3/9
18/21 + 12/9 is 46/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
18/21 = 18 × 3/21 × 3 = 54/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Add the two like fractions:
54/63 + 84/63 = 54 + 84/63 = 138/63 - 138/63 simplified gives 46/21
- So, 18/21 + 12/9 = 46/21
In mixed form: 24/21
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